Ellipsoid Volume Calculator (m³, L)
Calculate the volume of an ellipsoid in cubic meters and liters from its three semi-axes.
How to Calculate Ellipsoid Volume
Compute the volume of an ellipsoid...
Percent Difference Calculator
Calculate percent change, percent difference, or increase or decrease a number by a given percentage with formulas shown.
Compute the percent change, the percent difference,...
Morse Code Translator
Translate text to Morse code or decode pasted dots, dashes, spaces and slashes back to text.
This translator is for quick Morse practice, radio-message examples...
Pool Volume Calculator
Estimate pool volume in US gallons, liters, cubic meters and cubic feet for round, oval, rectangle, kidney, L-shape and sectioned pools, with filter turnover,...
Bitwise Operator Calculator
Calculate AND, OR, XOR, NOT and bit shifts for decimal, hex or binary integers.
Enter the example value or paste your own input, choose the...
URL Encoder and Decoder
Encode or decode URLs, query values and special characters using browser-safe URL rules.
Paste your value, choose the mode if the calculator has one, and...
CSS Font Display Checker
Paste CSS and check @font-face blocks for font-display, src, woff2 usage and blocking-risk patterns.
This checker is for frontend performance QA when custom fonts are...
Affiliate Commission Calculator
Estimate affiliate commission, approved sales and earnings per click from traffic, conversion and approval assumptions.
This calculator helps forecast affiliate revenue before or after a...
JSON Minifier
Remove whitespace from valid JSON and compare original size with the minified result.
Paste your value, choose the mode if the calculator has one, and...
Pythagorean Theorem Calculator
Pythagorean Theorem Calculator. Enter your own values first; presets below the fields are editable examples.
How to useEnter your own values first; presets below the...
Change MP3 Volume Online
Make an MP3 quieter or louder in the browser with exact percent control and local MP3 output.
How to use itAdd an MP3, choose the...
m/s to km/h calculator
Convert m/s to km/h with a focused calculator, examples and visible formula.
Convert m/s to km/h with a focused calculator, examples and visible formula.The widget...
Compound Interest Calculator
Project the growth of savings with compounding, contributions and year-by-year breakdown.
This compound interest calculator projects how an investment grows when interest is reinvested each...
CIDR Subnet Splitter
Split an IPv4 CIDR block into smaller subnets with a longer prefix length.
Enter the example value or paste your own input, choose the mode...
Trim Video Online
Cut MP4, MOV or WEBM video in the browser with preview, exact seconds and local MP4 output.
How to use itAdd a video file, wait...
HMAC SHA-256 Generator
Create an HMAC digest from a message and secret key with SHA-256, SHA-384 or SHA-512.
Paste your value, choose the mode if the calculator has...
YAML to JSON Converter
Convert YAML to JSON or JSON to YAML locally in the browser using a bundled parser.
This converter turns pasted YAML into formatted or compact...
Sand Calculator
Estimate sand for paver bedding, sandbox fill, pool bases, mortar, and polymeric paver joints — yards, tons, and 50 lb bag counts with rectangle,...
IP Range to CIDR Converter
Convert an IPv4 start-end range into the smallest list of CIDR blocks.
Enter the example value or paste your own input, choose the mode when...
Set Operations Calculator
Calculate union, intersection, difference and symmetric difference for two comma-separated sets.
Paste your value, choose the mode if the calculator has one, and use the...
Square Centimeters Calculator
Compute area in cm² from rectangle, circle, triangle, trapezoid, parallelogram, and regular polygon dimensions.
Square centimeters (cm²) measure area, not length. Use this calculator for...
Port Number Lookup
Look up common TCP and UDP port numbers or find a port by service name.
Enter the example value or paste your own input, choose...
Bucket Volume Calculator (fl oz, gal)
Calculate the volume of a bucket in fluid ounces and gallons from its dimensions.
How to Calculate Bucket Volume in Imperial Units
Determine bucket capacity in...
IP CIDR Overlap Checker
Check whether two IPv4 CIDR blocks overlap and show their address ranges.
Enter the example value or paste your own input, choose the mode when...
Ideal Weight Calculator
Find the healthy weight range for your height and body frame, compare four classic formulas with the healthy BMI band, and see how far...
Rectangular Prism Volume Calculator
Compute volume of a box or rectangular prism in m³, L, ft³, or gallons.
Enter length, width, and height — in meters, centimeters, millimeters, inches,...
Tint Photo Online
Add a color tint to JPG, PNG, WEBP and AVIF photos locally in the browser with blend mode, color picker and preview.
How to use...
Base64 Text Encoder and Decoder
Encode plain text to Base64 or decode Base64 back to readable UTF-8 text in the browser.
Paste your value, choose the mode if the calculator...
Frying Pan Volume Calculator (fl oz, gal)
Calculate the volume of a frying pan in fluid ounces and gallons from its dimensions.
How to Calculate Frying Pan Volume in Imperial Units
Determine frying...
SemVer Compare Calculator
Compare two semantic version strings and show which one is newer according to SemVer ordering.
Paste your value, choose the mode if the calculator has...
Vertical Conical Tank Volume (gal, ft³)
Calculate volume and fill level of a vertical tank with conical bottom in gallons and cubic feet.
How to Calculate Vertical Conical Tank Volume in...
TOTP Code Generator
Generate a current time-based one-time password from a Base32 secret locally in the browser.
Enter the example value or paste your own input, choose the...
JSON Flatten Tool
Flatten nested JSON into dot paths or rebuild a simple object from flattened key-value pairs.
Enter the example value or paste your own input, choose...
Logic Gate Calculator
Calculate the output of common digital logic gates from one or two binary inputs.
Paste your value, choose the mode if the calculator has one,...
Pipe Cross-Section Area Calculator
Compute inner cross-section flow area of a pipe from diameter or OD and wall thickness.
Find the internal flow area of a round pipe from...
Remove Empty Lines Online
Remove Empty Lines Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Meters to Cubic Meters Converter — V = L × W...
Convert length, width, and height in meters directly to cubic meters (m³). Instant equivalents in liters, ft³, in³, gallons.
Convert three dimensions in meters directly...
Blur Photo Edges Online
Blur Photo Edges Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Compress Video Online
Reduce video size locally in the browser by choosing quality and maximum width, then save a smaller MP4.
How to use itAdd a video, choose...
Barrel Water Volume Calculator (gal, ft³)
Calculate the volume of water in a barrel using imperial units (gallons, cubic feet).
How to Calculate Barrel Volume in Imperial Units
This calculator computes barrel...
PDF to JPG Converter
Convert PDF pages to JPG in your browser with multiple PDFs, page ranges, scale, quality settings and ZIP download.
How to use itAdd one or...
Sitemap XML Audit Tool
Paste a sitemap XML file or URL list and check protocol limits, duplicate loc values, dates and URL scope.
This tool is meant for quick...
Price per Square Foot Calculator
Convert between total price, area in ft², and price per square foot.
Work out the price per square foot from a total amount and an...
Bit Mask Calculator
Build a bit mask from positions and show the result as binary, decimal and hexadecimal.
Paste your value, choose the mode if the calculator has...
Adjust Photo Exposure Online
Adjust photo exposure in the browser with brighter or darker output, shadows, gamma, preview and batch processing.
How to use itAdd images and set exposure....
Marketplace VAT-Inclusive Price Calculator
Calculate the net price, VAT amount and contribution profit from a VAT-inclusive marketplace sale price.
Use this calculator when the customer-facing price already includes VAT...
Text Case Converter
Convert text between lowercase, uppercase, title case, camelCase, snake_case and kebab-case.
Paste your value, choose the mode if the calculator has one, and use the...
XML Formatter and Validator
Validate XML and pretty-print it with indentation for easier reading.
Enter the example value or paste your own input, choose the mode when one is...
Air Freight Chargeable Weight Calculator
Calculate air freight chargeable weight from carton count, dimensions, gross weight, volumetric divisor and rate.
Air freight often bills by the greater of actual gross...
GitHub Actions Matrix Counter
Estimate GitHub Actions matrix job counts from pasted matrix JSON or YAML-like axis lists.
This counter helps review CI cost and queue size before changing...
Retro Photo Online
Retro Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...
Barrel Water Volume Calculator (m³, L)
Calculate the volume of water in a barrel using metric units (liters, cubic meters).
How to Calculate Barrel Volume
This calculator determines the volume of a...
Data URI Encoder and Decoder
Create a Base64 data URI from text or decode a data URI back into its media type and payload.
Paste your value, choose the mode...
Bowl Volume Calculator (mL, L)
Calculate the volume of a bowl in milliliters and liters from its dimensions.
How to Calculate Bowl Volume
This calculator computes the internal volume of a...
Basal Metabolic Rate (BMR) Calculator
Estimate the calories your body burns at complete rest, compare three BMR formulas and turn the result into a daily calorie target.
To get a...
Boolean Truth Table Generator
Generate a truth table for a simple Boolean expression with variables such as A, B and C.
Paste your value, choose the mode if the...
Product Photo Crop Online
Prepare product-card photos in your browser with square and vertical sizes, crop or fit mode, batch queue and ZIP download.
How to use itAdd photos,...
YAML Formatter and Validator
Validate pasted YAML and format it with consistent indentation using a local browser parser.
This tool validates pasted YAML and rewrites it with consistent indentation....
Levenshtein Distance Calculator
Calculate edit distance between two strings and estimate their similarity percentage.
Enter the example value or paste your own input, choose the mode when one...
IEEE 754 Float Converter
Convert decimal numbers to IEEE 754 float hex or decode 32-bit float hex back to a number.
Enter the example value or paste your own...
Blur Part of Photo Online
Hide a selected photo area in the browser with blur, pixelation or solid fill without AI and without uploading files.
How to use itAdd a...
One-Rep Max (1RM) Calculator
Estimate your one-rep max from any submaximal set, compare six prediction formulas and get a full percent-of-1RM training table with a warm-up plan.
To get...
Round Photo Corners Online
Round corners of JPG, PNG, WEBP and AVIF photos in your browser with radius control, preview and ZIP download.
How to use itAdd images and...
QR Code Generator
Generate a browser-side SVG QR code from a URL, text, email address or phone number.
This tool creates a QR code from text you enter...
Slope Percent to Degrees
Convert slope percent to angle in degrees with ratio and mm/m equivalents.
Turns a slope given in percent into the equivalent angle in degrees using...
DNS TTL Calculator
Convert DNS TTL seconds into readable time and estimate cache time remaining after a record change.
Enter the example value or paste your own input,...
UTF-8 Byte Counter
Count UTF-8 bytes, Unicode code points and JavaScript string units for pasted text.
Paste your value, choose the mode if the calculator has one, and...
Lean Body Mass Calculator
Estimate your lean body mass in kilograms and pounds from your sex, height and weight, or from a known body-fat percentage, and see how...
Slope From Two Points Calculator
Slope From Two Points Calculator. Enter your own values first; presets below the fields are editable examples.
How to useEnter your own values first; presets...
Online Tally Counter – Click Counter Tool
Count clicks, items, people or repetitions with large plus and minus buttons and saved values in this browser.
Use the counter
Press the large plus button...
Nginx Access Log Analyzer
Paste Nginx access log lines and summarize status codes, methods, paths, IPs, bytes and slow requests locally.
This analyzer is for quick server-log triage when...
Service Worker Cache Audit
Paste service worker JavaScript and audit cache naming, install, activate, fetch and old-cache cleanup patterns.
This audit is for developers checking a service worker before...
Resize Video Online
Resize Video Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...
GST Calculator
Calculate GST inclusive or exclusive price for India, Australia, Canada, NZ and more.
This GST calculator works for every major Goods and Services Tax regime:...
Binary Search Steps Calculator
Estimate the maximum comparisons needed for binary search over a sorted collection.
Enter the example value or paste your own input, choose the mode when...
Nth Root Calculator
Calculate any root — square, cube, or nth — with decimal precision and exact form, for any index from 2 to 32.
This tool computes...
Blood Alcohol Content Calculator
Estimate your blood alcohol content from sex, body weight, the number of standard drinks and how long ago you started, then see a sober-up...
Sleep Cycle Calculator
Find the best times to go to bed or wake up by aligning your night to 90-minute sleep cycles, with the total sleep for...
Compare Two Texts Online
Compare two pasted texts or two TXT, MD or DOCX files in the browser and download a difference report.
How to use itPaste text into...
DPI Calculator
Calculate screen PPI, effective print DPI, and the pixel dimensions required for any print size.
DPI calculator that handles three jobs in one place. Screen...
MAC Address Formatter
Validate and reformat a MAC address as colon, hyphen, dot and plain hex notation.
Paste your value, choose the mode if the calculator has one,...
SPF Record Checker
Paste an SPF TXT value and check syntax, mechanisms, all policy, redirect and estimated DNS lookup count.
This local checker helps read an SPF record...
IPv4 Integer Converter
Convert an IPv4 address to its unsigned integer value and convert integers back to dotted IPv4.
Paste your value, choose the mode if the calculator...
Horizontal Oval Tank Volume (m³, L)
Calculate volume and fill level of a horizontal oval (stadium-shaped) tank in liters and cubic meters.
How to Calculate Horizontal Oval Tank Volume
Compute volume of...
Heart Rate Zone Calculator
Work out your five training heart-rate zones in bpm from your age, sex and resting heart rate, and see how much time to spend...
Freelance Hourly Rate Calculator
Work out the hourly rate you need to charge as a freelancer to hit a target take-home income after expenses and tax, or check...
Morse Code Timing Calculator
Calculate Morse dot, dash, spacing and message duration from WPM and Farnsworth speed.
This calculator turns Morse speed settings into practical timing values. Enter a...
App Store Commission Calculator
Estimate app store net proceeds from customer price, commission, payout fees, refunds and withholding assumptions.
Use this calculator when you know the customer price and...
WEBP to JPG Converter
Convert WEBP files to JPG in your browser with batch upload, presets and ZIP download.
How to use itDrop your WEBP files into the upload...
Gitignore Pattern Tester
Paste .gitignore patterns and file paths to see which files would be kept or ignored.
This tester helps debug .gitignore rules before committing generated files,...
AVIF to PNG Converter
Convert AVIF files to PNG in your browser with batch upload, presets and ZIP download.
How to use itDrop your AVIF files into the upload...
UTM URL Builder
Build a tagged campaign URL with utm_source, utm_medium, utm_campaign, utm_content and utm_term.
This builder is for marketers and site owners who need a clean campaign...
Add Signature to PDF Online
Add Signature to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Fourth Root Calculator
Compute the fourth root of a number with step-by-step formula ⁴√x = x^(1/4) = √(√x).
Enter any number to get its fourth root (⁴√x) to...
DMARC Record Checker
Paste a DMARC TXT value and check policy, reporting address, alignment mode and RFC 9989-era tags.
This checker helps read a DMARC record in plain...
Batch Rename Files Online
Rename many files in the browser using a pattern with numbering while keeping the original files unchanged.
How to use itAdd files, enter a name...
Black and White Photo Online
Turn photos black and white in the browser with preview, batch processing and ZIP download.
How to use itAdd images and check the before-and-after preview....
MP4 to MP3 Online
Extract audio from an MP4 video and save it as MP3 in the browser with bitrate control and local processing.
How to use itAdd an...
SHA-256 Hash Generator
Generate SHA-1, SHA-256 and SHA-512 hashes for pasted text using the browser crypto API.
Paste your value, choose the mode if the calculator has one,...
Hex Text Converter
Convert text to hexadecimal bytes or decode a hex byte string back to UTF-8 text.
Enter the example value or paste your own input, choose...
Wholesale to Retail Price Calculator
Convert wholesale unit cost into a retail price using target margin or markup plus landed cost assumptions.
This calculator helps turn wholesale cost into a...
Set-Cookie Attribute Checker
Paste Set-Cookie headers and check Secure, HttpOnly, SameSite, Partitioned and prefix rules.
Cookie mistakes are easy to miss in raw headers. This checker reviews each...
Two-Thirds of a Number Calculator
Compute two thirds of any number as decimal, fraction, and rounded values.
This calculator returns two-thirds of any number you enter and shows the result...
Sheet Area Calculator
Compute total area of flat sheets from length, width, and count in m² or ft².
Calculate the area of rectangular sheets — drywall, plywood, OSB,...
Post Hole Concrete Calculator
Estimate concrete bags per post hole — round or square hole, optional 4×4 or 6×6 post displacement, 5 bag sizes, frost-depth notes.
Why the post...
Resource Hints Checker
Paste HTML head markup and check preload, preconnect, dns-prefetch, prefetch and modulepreload hints.
This checker is for frontend performance QA when resource hints have been...
ZIP File Manifest Viewer
Inspect a ZIP file locally and copy a manifest table of entries, sizes and modified dates.
This tool reads a ZIP archive in the browser...
Remove Noise from Audio Online
Reduce background noise in audio locally: rumble filter, soft noise gate, normalization and MP3 export.
How to use itAdd a recording, choose background reduction strength...
Dimensional Weight Comparison Calculator
Compare actual weight with dimensional weight under two divisor assumptions and estimate the billable-weight difference.
Dimensional weight charges a shipment for the space it occupies...
Retirement Savings Calculator
Project how large your retirement savings could grow, or work out the monthly contribution needed to reach a target balance by retirement age.Start with...
Horizontal Elliptic Tank Volume (gal, ft³)
Calculate volume and fill level of a horizontal tank with elliptical cross-section in gallons and cubic feet.
How to Calculate Horizontal Elliptic Tank Volume in...
Marketplace Minimum Sale Price Calculator
Calculate the minimum marketplace sale price in USD needed to cover costs, percentage fees and target profit.
Use this calculator before setting a listing price....
TDEE Calculator (Total Daily Energy Expenditure)
Estimate your Total Daily Energy Expenditure in calories, see the burn split into BMR, NEAT, training and digestion, and get cut, maintain and bulk...
Compress PDF Online
Reduce PDF size in the browser by locally redrawing pages with JPEG quality and scale controls.
How to use itAdd a PDF, choose JPEG quality...
Click Counter
Tally counter with keyboard shortcuts, custom step, and saved value.
A browser-based tally counter that keeps a running total you control with large buttons or...
Thousand to Million Converter
Convert between thousand (K), million (M), and Indian lakh numbers.
Convert any number between thousands (K) and millions (M) with one divide-by-1,000 step — the...
PNG to JPG Converter
Convert PNG files to JPG in your browser with batch upload, presets and ZIP download.
How to use itDrop your PNG files into the upload...
Fraction Calculator
Add, subtract, multiply, and divide two fractions with step-by-step explanation, automatic simplification, and mixed, improper, and decimal result views.
This fraction calculator performs the four...
HEIC to PNG Converter
Convert HEIC/HEIF files to PNG in your browser with batch upload, presets and ZIP download.
How to use itDrop your HEIC/HEIF files into the upload...
Certificate of Deposit CD Calculator
Work out the maturity value, total interest and effective annual yield of a fixed-term certificate of deposit, and compare how daily, monthly, quarterly and...
Braille Text Converter
Convert plain English text to uncontracted Unicode Braille cells or decode simple Braille letters back to text.
This converter is for simple Braille pattern checks...
Atbash Cipher Translator
Mirror A-Z text with the Atbash cipher while keeping numbers, spaces and punctuation in place.
This browser-side translator applies the Atbash mirror alphabet to pasted...
Mulch Calculator
Estimate mulch in cubic yards and 2 or 3 cu ft bags by shape, depth, and area — rectangle, circle, L-shape, tree-ring donut, or...
Wire Size Calculator
Size electrical wire by ampacity and voltage drop. Shows both AWG and metric mm² recommendations for copper or aluminum conductors.
The Wire Size Calculator determines...
Bowl Volume Calculator (fl oz, gal)
Calculate the volume of a bowl in fluid ounces and gallons from its dimensions.
How to Calculate Bowl Volume in Imperial Units
Determine how much liquid...
A/B Test Sample Size Calculator
Estimate A/B test sample size and test duration from baseline conversion, lift, confidence and power.
This calculator estimates the sample size needed per variant for...
Roman Numeral Converter
Convert numbers from 1 to 3999 into Roman numerals or validate and decode a Roman numeral.
This converter is for dates, outlines, classroom exercises and...
Center Focus Photo Online
Center Focus Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Net Worth Calculator
Add up everything you own and everything you owe to see your net worth, with an itemised breakdown of which assets and debts dominate...
Student Loan Payoff Calculator
See when your student loan will be paid off and how much interest it will cost, then find how much faster an extra monthly...
cm² to m² calculator
Convert cm² to m² with a focused calculator, examples and visible formula.
Convert cm² to m² with a focused calculator, examples and visible formula.The widget...
Sphere Volume Calculator (gal, ft³)
Calculate the volume of a sphere in gallons and cubic feet from its radius or diameter.
How to Calculate Sphere Volume in Imperial Units
Determine sphere...
Luhn Checksum Calculator
Validate a number with the Luhn algorithm or calculate the check digit for a partial number.
Enter the example value or paste your own input,...
Change PDF Page Size Online
Change PDF Page Size Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Add Border to Photo Online
Add a border or frame to photos in the browser with width, color, rounding, inside/outside mode and ZIP download.
How to use itAdd photos, choose...
MD5 Hash Generator
Generate an MD5 digest for pasted text and compare the output length with common hash formats.
Enter the example value or paste your own input,...
Video to GIF Online
Create a GIF from MP4, MOV or WEBM in the browser with start/end time, width and FPS controls.
How to use itAdd a video, set...
Adjust Photo Saturation Online
Adjust photo saturation in the browser from muted to vivid, with exact percentage control and local processing.
How to use itAdd images and set saturation....
Matrix Calculator
Perform matrix addition, subtraction, multiplication, scalar multiplication, determinant, inverse, transpose and rank in one tool.
This matrix calculator combines eight common linear-algebra operations into a...
Geschwindigkeitsrechner
Convert between m/s, km/h, mph, knots, ft/s, ft/min, cm/s, mm/s, Mach, km/s and mi/min with instant bidirectional output and click-to-copy values.
Speed Converter handles eleven...
Number Base Converter
Convert integers between binary, octal, decimal, hexadecimal and any base from 2 to 36, with step-by-step math, bitwise operations and two's complement view.
This number...
TSV to CSV Converter
Convert tab-separated values to comma-separated CSV with proper quoting.
Paste your value, choose the mode if the calculator has one, and use the first result...
Smoking Cost Calculator
Work out how much smoking costs you per day, week, month and year from your own pack price, then see what it adds up...
Pixels to Millimeters Converter
Convert pixels to millimeters at 72, 96, 150, or 300 DPI.
This converter turns pixel measurements into millimeters using the standard formula mm = px...
Trim Audio Online
Cut MP3, WAV, M4A or OGG audio in the browser with waveform selection and MP3 output.
How to use itAdd an audio file, preview the...
WCAG Color Contrast Checker
Enter foreground and background colors to check WCAG contrast ratios for normal text, large text and UI elements.
This checker is for designers, developers and...
Geometry Shape Builder
Draw triangles, quadrilaterals, circles, and segments — see angles, lengths, area.
Interactive geometry tool that draws shapes from coordinates and reports every measurement at once....
IP CIDR Calculator
Calculate IPv4 network address, broadcast address, usable host range and address count from CIDR notation.
Paste your value, choose the mode if the calculator has...
Rent vs Buy Calculator
Compare the total cost of renting against buying a home over the years you plan to stay, and find the breakeven year when buying...
Merge CSV Files Online
Merge CSV Files Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Split TXT File Online
Split TXT File Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Combine Photos Into One Online
Combine several JPG, PNG, WEBP or AVIF photos into one image in your browser with side-by-side, vertical or grid layout.
How to use itAdd two...
OpenAPI Spec Summary
Paste OpenAPI JSON and summarize paths, operations, schemas, security schemes and common documentation gaps.
This tool is for quickly understanding an OpenAPI document before a...
JPG to WEBP Online
Convert JPG images to WEBP in your browser with batch processing, quality control and ZIP download.
How to use itAdd JPG files, choose WEBP quality...
NATO Phonetic Alphabet Converter
Convert letters and numbers to NATO phonetic words or decode phonetic words back to plain text.
This converter helps spell names, ticket IDs, call signs...
CSV Deduplicate Rows Tool
Remove duplicate CSV rows while optionally keeping the header row at the top.
Enter the example value or paste your own input, choose the mode...
Mortgage Calculator
Work out your full monthly mortgage payment, see how much interest the loan costs over its lifetime and check how extra payments shorten the...
Body Fat Percentage Calculator
Estimate body fat percentage with the US Navy tape, BMI-based or skinfold method, plus category, healthy range and fat and lean mass.
How to use...
Wood Cladding Calculator — boards, battens and cost estimate
Calculates the number of boards, battens, fixings and cost for wood cladding installation.
How to Use the Wood Cladding CalculatorThis calculator determines the quantity of...
Currency Converter
Convert an amount between two currencies using an exchange rate you enter, see the cost of the bank or exchange-service fee, and read off...
Saucepan Volume Calculator (mL, L)
Calculate the volume of a saucepan in milliliters and liters from its dimensions.
How to Calculate Saucepan Volume
This calculator computes saucepan capacity from internal diameter...
Split Image Into Grid
Upload an image, pick grid size, download each cell as a PNG.
This utility cuts any picture you already have on your device into an...
Mortgage Refinance Calculator
Check whether refinancing your mortgage saves money: see the verdict, the break-even month and a side-by-side comparison of your current loan and the new...
Email Header Analyzer
Paste raw email headers to summarize SPF, DKIM, DMARC, Received hops, delays and key message fields.
This analyzer is for support, deliverability and security triage...
Rectangular Tank Volume Calculator (gal, ft³)
Calculate the volume of a rectangular tank or box in gallons and cubic feet.
How to Calculate Rectangular Tank Volume in Imperial Units
Determine the volume...
Degrees to Slope Percent
Convert angle in degrees to slope percent with ratio and mm/m equivalents.
Enter an angle in degrees and get the slope as a percent, rise-to-run...
Inches to Feet Converter (with ft + in Split)
Convert inches to feet — decimal feet and the ft/in split (for example 68 in = 5 ft 8 in).
This converter turns inches (in)...
SRI Hash Generator
Paste JavaScript or CSS file contents and generate Subresource Integrity hashes plus script or link tags.
Use this when you pin a CDN script or...
File List to TXT Online
File List to TXT Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
HTML to PDF Online
HTML to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Pot Volume Calculator (mL, L)
Calculate the volume and capacity of a cooking pot in milliliters and liters.
How to Calculate Pot Volume
Compute the internal volume of a cooking pot...
Grade Average Calculator
Calculate a weighted grade average and the final-exam score needed for a target grade.
Grade Average Calculator
Calculate a weighted grade average and the final-exam score...
Before and After Photo Merge Online
Before and After Photo Merge Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd...
MX Record Priority Parser
Paste MX records and sort mail hosts by priority while flagging duplicates and failover concerns.
This parser is for quickly reading copied MX records from...
Markdown to HTML Preview
Render Markdown to sanitized HTML, preview the result and copy clean HTML.
This tool renders pasted Markdown into HTML and sanitizes the result in the...
Add Logo to Photo Online
Add a logo or image watermark to photos in the browser with position, size, opacity and batch processing.
How to use itAdd photos and a...
Savings Goal Calculator
Work out the monthly amount you need to save to hit a savings goal, how long an existing plan takes, or the balance your...
Maximum Heart Rate Calculator
Estimate your maximum heart rate in beats per minute from your age and sex, compare five age-based formulas side by side, and see the...
Remove Photo Metadata Online
Remove EXIF, GPS and camera metadata from images by re-saving JPG, PNG, WEBP or AVIF files in the browser.
How to use itAdd images and...
Replace Color in Photo Online
Replace Color in Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
MTU Packet Overhead Calculator
Estimate payload capacity, packet count and overhead percentage from MTU and header sizes.
Enter the example value or paste your own input, choose the mode...
Open Graph and Twitter Card Checker
Paste page head markup and review Open Graph plus Twitter Card fields for social previews.
This checker is for editors and developers who already have...
Bill Split Calculator
Work out exactly how much each person owes on a shared bill, including tip and tax, either split evenly or split by the items...
JSON Patch Generator and Tester
Generate RFC 6902 JSON Patch operations or apply a patch array to a JSON document.
This browser-side tool compares two JSON documents and generates a...
Retaining Wall Calculator
Estimate retaining wall block count, buried course, capstones, base and drainage gravel, perforated pipe, and filter fabric — with geogrid threshold warning.
How retaining wall...
Hash Table Load Factor Calculator
Calculate hash table load factor and estimate bucket count after resizing.
Enter the example value or paste your own input, choose the mode when one...
Calories Burned Calculator
Work out how many calories you burned during a specific activity and duration, see the burn per minute and per hour, and log a...
CSS Unit Converter
Convert common CSS length units such as px, rem, em, vw and vh using your root and viewport settings.
Paste your value, choose the mode...
Sales Tax Calculator
Add sales tax on top of a price, pull the tax back out of a tax-inclusive total, or total a shopping list and see...
Significant Figures Calculator
Significant Figures Calculator. Enter your own values first; presets below the fields are editable examples.
How to useEnter your own values first; presets below the...
Bar Chart Maker
Build a vertical or horizontal bar chart, edit labels and colors, copy the data table and download PNG.
How it worksAdd bars, enter a label...
Rail Fence Cipher Tool
Encode or decode a Rail Fence zigzag cipher with a chosen number of rails.
This tool applies the Rail Fence transposition cipher. Enter a message,...
Big O Growth Calculator
Compare estimated operation growth for common complexity classes as input size changes.
Enter the example value or paste your own input, choose the mode when...
Tax Refund Estimator
Compare the tax already taken from your pay during the year against the tax actually due to see whether you are owed a refund...
Delete PDF Pages Online
Remove selected pages from PDF files in your browser with page ranges, thumbnails and local PDF download.
How to use itAdd a PDF and wait...
Black Out Area in PDF Online
Black Out Area in PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd...
CSP Hash and Nonce Helper
Paste inline JavaScript or CSS and generate CSP SHA-256 hash entries and example nonce markup.
This helper is for a specific Content-Security-Policy task: replacing unsafe...
CSS Clamp Calculator
Generate a copy-ready CSS clamp() declaration for fluid typography, spacing or layout values.
This calculator turns minimum and maximum sizes plus viewport bounds into a...
Crop PDF Online
Crop PDF margins in the browser with millimeter controls, page ranges, thumbnails and local download.
How to use itAdd a PDF and set margins from...
API Key Log Redactor
Paste logs or config snippets and redact likely provider keys, bearer tokens, passwords, private keys and emails locally.
Use this before sharing logs in a...
Asphalt Calculator
Estimate hot-mix asphalt in tons, cubic yards, and truckloads for driveways, parking pads, resurfacing, and pothole patches — with density-aware math and a 10%...
AVI to MP4 Online
AVI to MP4 Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
P-value Calculator
P-value Calculator. Enter your own values first; presets below the fields are editable examples.
How to useEnter your own values first; presets below the fields...
Yards to Feet Converter
Yards to feet converter with exact 3 ft per yard ratio, football field references, fabric and landscape use cases, and a reverse feet to...
Cylinder Volume Calculator
Compute cylinder volume from diameter or radius and height in multiple units.
Compute the internal volume of any right circular cylinder from its diameter (or...
Unicode Code Point Converter
Convert characters to Unicode code points, UTF-8 bytes and HTML numeric entities.
Enter the example value or paste your own input, choose the mode when...
Image EXIF Metadata Viewer
Read image EXIF and metadata locally, then copy a concise metadata table.
This viewer reads image metadata in the browser and turns it into a...
Uptime SLA Downtime Calculator
Convert an uptime SLA percentage into allowed downtime over a selected period.
Enter the example value or paste your own input, choose the mode when...
HAR File Summary Tool
Paste or upload a HAR file and summarize request count, status buckets, hosts, MIME types and slow requests.
This browser-side tool is for quick HAR...
Add Text to Photo Online
Add captions to JPG, PNG, WEBP and AVIF photos in the browser with position, color, size, background and ZIP download.
How to use itAdd images,...
MIME Type Lookup
Look up common MIME types by file extension or find the usual extension for a MIME type.
Paste your value, choose the mode if the...
HTTP Header Parser
Parse raw HTTP headers into normalized name-value pairs and highlight duplicates.
Enter the example value or paste your own input, choose the mode when one...
Rectangular Tank Volume Calculator (m³, L)
Calculate the volume of a rectangular tank or box in liters and cubic meters.
How to Calculate Rectangular Tank Volume
Compute the volume of a rectangular...
Feet to Inches Converter (with ft’in” Input)
Convert feet to inches — including ft'in" height input. 6 ft = 72 in; 5'8" = 68 in.
This converter turns feet (ft) into inches...
Inflation Calculator
See how the purchasing power of money changes over time: convert a past amount into today's money, or project what today's money will be...
Arccosine Calculator
Compute inverse cosine for input in with result in degrees or radians.
Compute the inverse cosine (arccos, acos, cos⁻¹) of any value x in...
Adjust Image Brightness and Contrast
Adjust brightness, contrast and saturation for JPG, PNG, WEBP and AVIF images in your browser with preview and ZIP download.
How to use itAdd images...
Paver Calculator
Estimate paver count by pattern, plus base gravel, bedding sand, polymeric joint sand, edge restraint and landscape fabric — the full patio material kit...
WAV to MP3 Online
Convert WAV audio to MP3 in the browser with bitrate control and no server upload.
How to use itAdd a WAV file, choose MP3 quality...
Circle Crop Photo Online
Create a round photo or avatar in the browser with circular mask, zoom, X/Y shift and transparent PNG/WEBP output.
How to use itAdd a photo,...
Tangent Calculator
Calculate tan of any angle in degrees or radians with exact common values.
This tool evaluates the tangent of any angle, accepting input in degrees...
Parabola Graph Plotter
Plot y = ax² + bx + c with vertex, roots, axis of symmetry, and SVG graph.
Enter the coefficients a, b, c of a...
Env File Diff Checker
Compare two .env-style files by variable name and see missing, extra and shared keys without showing secret values.
This tool is for deployment reviews where...
HTML Entities Encoder and Decoder
Encode text as HTML entities or decode common entities back to readable characters.
Paste your value, choose the mode if the calculator has one, and...
Canonical and Meta Robots Checker
Paste HTML and response headers to check canonical links, robots meta tags, X-Robots-Tag and conflicts.
This checker is for page-level SEO debugging when a source...
WEBM to MP4 Online
WEBM to MP4 Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
LLM Token Counter and API Cost Calculator
Estimate tokens and API cost for GPT, Claude, Gemini, Llama and Mistral from any prompt. Per-model pricing, context window usage and total-cost calculator.
This calculator...
JSON Formatter and Validator
Validate JSON, format it with indentation or minify it into a compact one-line string.
Paste your value, choose the mode if the calculator has one,...
Endianness Converter
Reverse byte order for a hex value and compare big-endian and little-endian integer interpretations.
Enter the example value or paste your own input, choose the...
MOV to MP4 Online
MOV to MP4 Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Calorie Deficit Calculator
Work out how many calories to eat per day to reach a goal weight, with a target date and a weekly weight chart that...
M4A to MP3 Online
Convert M4A audio files to MP3 locally in the browser with simple quality presets and exact bitrate.
How to use itAdd an M4A file and...
Marketplace Cross-Border Landed Cost Calculator
Calculate cross-border landed cost per unit in USD using item value, freight, insurance, duty, tax, brokerage and FX buffer.
For imported inventory, the purchase price...
JSON-LD Structured Data Checker
Paste JSON-LD or HTML and check syntax, graph items, duplicate @id values and common type fields.
This checker is for fast local inspection of structured...
HTML Minifier
Remove comments and extra whitespace from an HTML snippet for compact copying.
Enter the example value or paste your own input, choose the mode when...
Marketplace Commission Comparison Calculator
Compare seller profit under different marketplace commission rates using the same price, COGS, shipping and ad cost.
Use this calculator when a category, plan or...
Bundle Kit Margin Calculator
Calculate bundle kit margin from component costs, packaging, assembly labor, fulfillment and selling fees.
This calculator measures the margin of one sellable bundle or kit....
Find Difference Between Photos Online
Find Difference Between Photos Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
PPI and DPI Calculator
Calculate pixel density from screen or image resolution and diagonal size.
Paste your value, choose the mode if the calculator has one, and use the...
Price per Square Meter Calculator
Convert between total price, area in m², and price per square meter.
This tool converts between three values that any buyer, landlord or contractor needs:...
Film Effect Photo Online
Film Effect Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Invert Image Colors Online
Invert image colors in your browser to create a negative effect with preview, batch processing and ZIP.
How to use itAdd images and check the...
Grade Percentage Calculator
Convert between percent, US letter grade, and 4.0 scale GPA.
Look up what a percent score maps to on the standard US 10-point scale and...
Add Shadow to Photo Online
Add a soft drop shadow to photos or transparent PNG objects in the browser with blur, X/Y offset and color.
How to use itUpload an...
JPG to PNG Converter
Convert JPG/JPEG files to PNG in your browser with batch upload, presets and ZIP download.
How to use itDrop your JPG/JPEG files into the upload...
Paving Stones Calculator — Pieces per m² and Total Quantity
Calculate how many paving stones or tiles you need per square meter and the total quantity for your project.
This calculator determines the number of...
ISBN Checksum Calculator
Validate ISBN-10 or ISBN-13 values and calculate the expected check digit.
Enter the example value or paste your own input, choose the mode when one...
Vigenere Cipher Tool
Encode or decode a Vigenere cipher message with a repeating alphabetic key.
This tool is for classroom cryptography exercises, puzzle checks and examples where a...
Cost-of-Living Comparison Calculator
Compare living costs between your current location and a destination and find the equivalent income you would need to keep the same standard of...
Random Password Generator
Generate random passwords from selected character sets and estimate their entropy.
Enter the example value or paste your own input, choose the mode when one...
Cotangent Calculator
Calculate cot of any angle in degrees or radians with exact common values.
This tool computes the cotangent of an angle using cot(θ) = cos(θ)...
Pace Calculator
Running pace calculator with distance, time, speed, split tables and Riegel finish-time predictions.
This running pace calculator works in three directions: enter distance and time...
Volume to Area Calculator (m³ ↔ m²)
Convert any volume to floor area for a given depth: m³, cm³, mm³, dm³, L, ft³, in³, yd³, US/UK gal → m², cm², dm²,...
Caesar Cipher Brute Force Decoder
Try every Caesar shift from 1 to 25 and compare all decoded candidates at once.
This decoder is for Caesar messages when the shift is...
Marketplace ROAS Profit Calculator
Calculate marketplace campaign ROAS, net profit and break-even ROAS from revenue, ad spend, COGS, fees and returns.
ROAS by itself does not show profit. This...
Add Stamp to PDF Online
Add Stamp to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
CORS Header Checker
Check pasted CORS response headers against an origin, method and credential mode.
Enter the example value or paste your own input, choose the mode when...
Marketplace Break-Even CPA Calculator
Calculate the break-even CPA in USD for a marketplace order after COGS, fees, shipping and return assumptions.
This calculator finds how much you can spend...
Cache-Control Header Analyzer
Paste HTTP response headers and interpret Cache-Control directives, TTLs, validators and cache hints.
This analyzer is for reading a single response header block from dev...
Pixels to Centimeters Converter
Convert pixels to centimeters at 72, 96, 150, or 300 DPI.
Convert any pixel value to centimeters, millimeters, and inches using the DPI (dots per...
Dropshipping Profit Calculator
Calculate dropshipping profit per order after supplier cost, shipping, transaction fees, ads and return risk.
Dropshipping margins can look healthy before shipping, ads and returns...
Add Padding to Photo Online
Add padding and canvas around an image in the browser with presets, exact pixels, color or transparent background and ZIP.
How to use itUpload images...
Modulo Calculator
Compute quotient, remainder, GCD, and modular exponentiation with three sign conventions and BigInt precision.
The Modulo Calculator computes a mod b for integers of any...
VAT Net/Gross Calculator
Add VAT, remove VAT from a gross price, or calculate the missing net/gross/tax amount.
VAT Net/Gross CalculatorAdd VAT, remove VAT from a gross price, or...
Protein Intake Calculator
Work out how many grams of protein you need per day from your body weight and goal, then see the amount in common foods...
m³ to tonnes calculator
Convert m³ to tonnes with a focused calculator, examples and visible formula.
Convert m³ to tonnes with a focused calculator, examples and visible formula.The widget...
Marketplace Return Rate Profit Calculator
Estimate expected marketplace profit per order after return rate, refund shipping, restocking and salvage assumptions.
Return rate is easy to underestimate. This calculator separates kept...
Accept-Language Header Parser
Parse an Accept-Language request header into sorted language preferences, q values and fallback notes.
This parser is for locale debugging when a browser, crawler or...
Matte Photo Online
Matte Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...
Change Audio Speed Online
Change Audio Speed Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Saucepan Volume Calculator (fl oz, gal)
Calculate the volume of a saucepan in fluid ounces and quarts from its dimensions.
How to Calculate Saucepan Volume in Imperial Units
Determine saucepan capacity in...
Marketplace Payment Processing Fee Calculator
Calculate marketplace payment processing fees in USD from order amount, order count, percentage rate and fixed fee.
Use this calculator when payment fees are the...
Paint Area on Photo Online
Paint a selected photo area in the browser with color, coordinates, size, opacity and batch processing.
How to use itAdd an image, choose a color...
Sort Files in ZIP Online
Sort Files in ZIP Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Redirect Header Chain Checker
Paste curl response headers and review redirect steps, Location headers, loops and final status.
This checker is for reviewing redirect behavior when you already have...
Reverse Audio Online
Reverse MP3, WAV, M4A or OGG audio locally in the browser with waveform preview and MP3 output.
How to use itAdd an audio file, check...
Add Music to Video Online
Add MP3, WAV, M4A or OGG music to a video locally with preview, volume controls and MP4 output.
How to use itAdd one video and...
Temperature Converter
Convert temperature between Celsius, Fahrenheit, Kelvin, Rankine, Réaumur, Delisle, Newton and Rømer — all eight scales at once with click-to-copy values.
The Temperature Converter displays...
A1Z26 Cipher Converter
Convert letters to A1Z26 number groups or decode 1-26 groups back to text.
This converter maps English letters to their alphabet positions, from A=1 through...
Color Palette From Photo Online
Color Palette From Photo Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Word, Character and Line Counter
Count words, characters, sentences and approximate reading time from pasted text.
Paste your value, choose the mode if the calculator has one, and use the...
GPA Calculator
Compute unweighted or weighted GPA on the 4.0 scale with credit hours and AP bonuses.
This GPA calculator converts letter grades into grade points on...
Text Diff Checker
Compare two text blocks line by line and show added, removed and unchanged lines.
Paste your value, choose the mode if the calculator has one,...
Cache Hit Ratio Calculator
Calculate cache hit ratio, miss ratio and saved origin requests from hit and miss counts.
Enter the example value or paste your own input, choose...
Square Millimeters to Square Meters Area Calculator
Convert rectangular dimensions in millimeters into area in square meters for drawings, panels, plates and PCBs.
For mm to m², use two dimensions in millimeters....
Text to PDF Online
Convert pasted text, TXT, Markdown or DOCX into a simple PDF in the browser with font size and margin controls.
How to use itPaste text...
Compress MP3 Online
Reduce MP3 file size in the browser by choosing a target bitrate and saving a new local MP3.
How to use itAdd an MP3, choose...
Image Aspect Ratio Calculator
Calculate an image aspect ratio and resize width or height while preserving proportions.
Paste your value, choose the mode if the calculator has one, and...
Gas Cylinder Volume Calculator (gal, ft³)
Calculate the internal volume of a gas cylinder in gallons and cubic feet.
How to Calculate Gas Cylinder Volume in Imperial Units
Determine the internal volume...
API Rate Limit Calculator
Translate an API rate limit into requests per second, planned runtime and safe pacing delay.
Enter the example value or paste your own input, choose...
Tap Code Converter
Convert text to tap-code row and column groups or decode tap-code pairs back to letters.
This converter is for the classic 5 by 5 tap...
Horizontal Cylinder Tank Volume (gal, ft³)
Calculate the volume and fill level of a horizontal cylindrical tank in gallons and cubic feet.
How to Calculate Horizontal Cylinder Volume in Imperial Units
Determine...
Add Vignette to Photo Online
Add a dark or colored vignette to photos in the browser with strength, light zone and edge color controls.
How to use itAdd photos, set...
Roofing Calculator: Squares, Bundles, Underlayment
Estimate roof surface area, squares, shingle bundles, underlayment rolls, drip edge and ridge cap from footprint and pitch.
From footprint to bundles — the three-stage...
CSV to JSON Converter
Convert CSV with a header row into a JSON array while preserving quoted fields.
Paste your value, choose the mode if the calculator has one,...
Create ZIP File Online
Create a ZIP archive from selected files directly in the browser without uploading them to a server.
How to use itAdd files, choose the archive...
GCF & LCM Calculator
Compute the greatest common factor and least common multiple of 2 to 10 positive integers, with step-by-step Euclidean algorithm and prime factorization.
This calculator finds...
Calorie Calculator
Daily calorie needs calculator with BMR, TDEE, goal-based targets and macronutrient breakdown in metric and imperial units.
This calorie calculator estimates daily energy needs from...
cURL Command Builder
Build a copyable curl command from method, URL, headers and optional request body.
Enter the example value or paste your own input, choose the mode...
Cloud Cost Calculator
Compare monthly AWS, Google Cloud, Azure, DigitalOcean and Linode bills for compute, storage, egress and managed database in one place.
The Cloud Cost Calculator estimates...
Torus Volume Calculator (m³, L)
Calculate the volume of a torus (donut shape) in cubic meters and liters.
How to Calculate Torus Volume
Compute the volume of a torus (donut/ring shape)...
Base58 Encoder and Decoder
Encode UTF-8 text as Bitcoin-style Base58 or decode Base58 back to text.
Enter the example value or paste your own input, choose the mode when...
Add Text to PDF Online
Add a text stamp to PDF pages in the browser with position, color, page range and local saving.
How to use itAdd a PDF, enter...
Cubic Yards to Cubic Feet Converter (yd³ to ft³)
Convert cubic yards to cubic feet and back. 1 yd³ = 27 ft³. Use for concrete, mulch, topsoil, and gravel delivery estimates.
Convert between cubic...
Sphere Volume Calculator (m³, L)
Calculate the volume of a sphere in cubic meters and liters from its radius or diameter.
How to Calculate Sphere Volume
Compute sphere volume using V...
Hamming Distance Calculator
Compare two equal-length strings or bit strings and count positions that differ.
Enter the example value or paste your own input, choose the mode when...
Posterize Photo Online
Posterize photos locally by limiting color levels, with preview, exact level control and ZIP download.
How to use itAdd images and choose 4, 8, 12...
CSV Column Extractor
Extract one column from CSV by header name or column number.
Enter the example value or paste your own input, choose the mode when one...
Gas Cylinder Volume Calculator (m³, L)
Calculate the internal volume of a gas cylinder in liters and cubic meters.
How to Calculate Gas Cylinder Volume
This calculator computes the internal volume of...
Age Calculator
Calculate exact age in years, months, days, hours and more from a birth date.
This age calculator takes your date of birth and an as-of...
Exponent Calculator
Compute x raised to the power y with exact big-integer results, scientific notation and step-by-step expansion. Includes reverse modes to find the base or...
PDF to Grayscale Online
PDF to Grayscale Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Character Frequency Counter
Count how often each character appears in a string and sort the frequency table.
Paste your value, choose the mode if the calculator has one,...
Income Tax Estimator
Estimate the income tax due on a gross annual salary using your own progressive tax bands or a flat rate, and see the take-home...
Marketplace Ad ACOS Break-Even Calculator
Calculate break-even ACOS, target ACOS and max CPC from sale price, product cost, fees, shipping and conversion rate.
ACOS is ad spend divided by ad-attributed...
Unzip File Online
Extract files from a ZIP archive in the browser and download the contents without sending the archive to a server.
How to use itAdd a...
Home Affordability Calculator
Find the maximum home price you can afford from your income, debts, down payment and rate, with a full monthly payment breakdown and three...
Bloom Filter Calculator
Calculate Bloom filter bit size and hash count from expected items and false-positive rate.
Enter the example value or paste your own input, choose the...
Gas Mileage MPG Calculator
Work out a vehicle's real fuel economy from the distance driven and the fuel used, shown at once as MPG, L/100 km and km/L.Start...
JPG to PDF Converter
Combine JPG and JPEG images into a PDF in your browser with batch upload, page size presets, margins and one PDF download.
How to use...
Square Feet to Square Yards Converter (ft² to yd²)
Convert square feet to square yards and back. 1 yd² = 9 ft². Use for carpet, fabric, landscaping, and US lot size estimates.
Convert between...
Marketplace Long-Term Storage Fee Calculator
Estimate long-term marketplace storage fees in USD from aged inventory, cubic feet, thresholds and your own surcharge rule.
This calculator helps decide whether aged inventory...
Retry-After Header Calculator
Convert a Retry-After header in seconds or HTTP-date format into a local retry time and wait duration.
This calculator is for API clients, crawlers and...
BMI Calculator
Body Mass Index calculator with metric and imperial units, color-coded category, healthy weight range and visual BMI scale.
This BMI calculator computes Body Mass Index...
Regex Replace Tester
Preview JavaScript regex replacement output with flags, capture groups and pasted sample text.
This tool previews a JavaScript regular expression replacement before you use it...
Markdown Table to CSV Converter
Convert a Markdown pipe table into CSV with quoted cells.
Enter the example value or paste your own input, choose the mode when one is...
Investment Return ROI Calculator
Work out the return on an investment: the total ROI percentage, the money gained, and the annualized year-on-year return, for a lump sum or...
Arcsine Calculator
Compute inverse sine for input in with result in degrees or radians.
Inverse sine (arcsin, sin⁻¹) returns the angle whose sine equals a given...
Marketplace Coupon Discount Margin Calculator
Calculate marketplace margin after coupons or discounts, including COGS, fees, shipping, ads and target profit.
Promotions can grow sales while shrinking contribution margin. This calculator...
Adler-32 Checksum Calculator
Calculate an Adler-32 checksum for text and show the value as hex and decimal.
Enter the example value or paste your own input, choose the...
Frying Pan Volume Calculator (mL, L)
Calculate the volume of a frying pan in milliliters and liters from its dimensions.
How to Calculate Frying Pan Volume
This calculator determines how much a...
TIFF to JPG Converter
Convert TIFF/TIF files to JPG in your browser with batch upload, presets and ZIP download.
How to use itDrop your TIFF/TIF files into the upload...
Million to Billion Converter
Convert between million, billion, trillion, and Indian lakh/crore on the short scale.
This converter turns an amount in one magnitude unit (thousand, million, billion, trillion,...
Subnet Mask and Wildcard Calculator
Convert between CIDR prefix length, subnet mask and wildcard mask for IPv4 networks.
Paste your value, choose the mode if the calculator has one, and...
Deck Board Calculator
Estimate deck board count, rows, linear feet, and fasteners by deck size, board length, gap, and material.
How decking math really works
A deck board order...
AVIF to JPG Converter
Convert AVIF files to JPG in your browser with batch upload, presets and ZIP download.
How to use itDrop your AVIF files into the upload...
Stair Calculator
Calculate risers, riser height, tread count, total run, stringer length, and IRC residential code checks for residential stairs.
How residential stair math works
A code-compliant stair...
One-Third of a Number Calculator
Compute one third of any number as decimal, fraction, and rounded values.
Find one-third of any number in four forms at once: the decimal to...
Cartons per Pallet Calculator
Estimate cartons per pallet from carton dimensions, pallet footprint, load height and weight limits.
Cartons per pallet depends on footprint, stack height and weight limits....
Marketplace Seller Net Profit Calculator
Calculate marketplace seller net profit in USD after COGS, selling fees, shipping, ads and expected returns.
Use this calculator before listing a product or changing...
Marketplace International Shipping Margin Calculator
Estimate marketplace profit after international shipping, landed charges, seller fees and payment buffers.
Cross-border orders can look profitable until shipping, handling, duties and payment risk...
GIF to MP4 Online
GIF to MP4 Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Multi-Pack Unit Price Calculator
Compare multi-pack unit price with a single-unit price after discounts, shipping, tax and unusable units.
This calculator helps decide whether a multi-pack is actually cheaper...
Macro Calculator (Protein, Carbs, Fat)
Convert a daily calorie target into grams of protein, carbs and fat, with diet presets, a protein floor check and a per-meal split.
Start by...
DMARC Aggregate XML Parser
Paste or upload a DMARC aggregate XML report and summarize counts, dispositions, pass/fail and source IPs.
This parser is for a quick read of a...
Base32 Encoder and Decoder
Encode text as RFC 4648 Base32 or decode a Base32 string back to UTF-8 text.
Enter the example value or paste your own input, choose...
Loan Calculator
Calculate loan EMI, total interest, amortization schedule, payoff date and extra-payment impact across 7 currencies.
Loan calculator that computes the Equated Monthly Installment (EMI), total...
Horizontal Hemispheric Tank Volume (gal, ft³)
Calculate volume and fill level of a horizontal tank with hemispherical ends in gallons and cubic feet.
How to Calculate Horizontal Hemispheric Tank Volume in...
Error Budget Burn Rate Calculator
Calculate SLO error budget, burn rate and projected exhaustion from traffic, errors, objective and time window.
This calculator is for SRE incident review and alert...
Marketplace Bundle Price Calculator
Calculate suggested marketplace bundle price from component costs, packaging, labor, shipping, fee rate and target margin.
Bundles can improve average order value, but they also...
File Size Converter
Convert file sizes between bytes, KB, MB, GB, KiB, MiB and GiB.
Paste your value, choose the mode if the calculator has one, and use...
Inches to Pixels Converter
Convert inches to pixels at 72, 96, 150, or 300 DPI.
Convert inches to pixels using the exact formula pixels = inches x DPI. The...
Waist-to-Hip Ratio Calculator
Work out your waist-to-hip ratio from two measurements, then see which World Health Organization risk band you fall into on a visual gauge.
To get...
Prime Factor Calculator
Primality check, prime factorization, and full divisor list for positive integers up to one trillion.
Check whether a number is prime, split any positive integer...
CSS Specificity Calculator
Calculate CSS selector specificity as ID, class/attribute/pseudo-class and element counts.
Enter the example value or paste your own input, choose the mode when one is...
tonnes to m³ calculator
Convert tonnes to m³ with a focused calculator, examples and visible formula.
Convert tonnes to m³ with a focused calculator, examples and visible formula.The widget...
Scientific Notation Calculator
Convert numbers between standard, scientific, engineering and E-notation. Parses any input format, rounds to significant figures and does arithmetic on two values.
Convert any number...
Photo Histogram Online
Photo Histogram Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...
Crop Video Online
Crop a video visually in the browser with a movable frame, aspect presets and local MP4 export.
How to use itAdd a video and move...
Aspect Ratio Calculator
Calculate aspect ratio from width and height, find a missing dimension from a known ratio, or proportionally scale any rectangle. Includes presets for 16:9,...
Photo Color Temperature Online
Make photos warmer or cooler in the browser with temperature, tint shift and quick balance buttons.
How to use itUpload photos, choose warmer, neutral or...
Horizontal Hemispheric Tank Volume (m³, L)
Calculate volume and fill level of a horizontal tank with hemispherical ends in liters and cubic meters.
How to Calculate Horizontal Hemispheric Tank Volume
Compute volume...
Flip Image Online
Flip images horizontally, vertically or both ways in your browser with preview, batch processing and ZIP.
How to use itAdd images and choose the flip...
CSP Report JSON Parser
Paste CSP violation report JSON and group violations by directive, blocked URI and document URL.
This parser is for reviewing Content Security Policy violation reports...
Tank Volume Calculator
Volume of cylindrical, rectangular, and capsule tanks with partial-fill support.
Compute the liquid capacity of a tank from its inner dimensions. Pick a shape —...
Split CSV File Online
Split CSV File Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
vCard QR Code Generator
Create a vCard contact payload and preview a QR code for phones, email, company and website.
This generator builds a vCard contact payload and previews...
CSP Directive Checker
Parse a Content-Security-Policy header and flag important missing baseline directives.
Enter the example value or paste your own input, choose the mode when one is...
Digital Product Marketplace Payout Calculator
Calculate a digital product marketplace payout in USD after commission, processing fees, refunds and reserve holds.
Use this calculator to estimate creator payout from digital...
Extract Frame From Video Online
Extract Frame From Video Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Marketplace Price Parity Calculator
Calculate the marketplace price needed to match direct-store profit after fees, COGS, shipping and ad cost.
Price parity is not just matching the sticker price....
JWT Decoder
Decode a JWT header and payload locally without sending the token to a server.
Paste your value, choose the mode if the calculator has one,...
ULID Generator
Generate sortable ULID identifiers and decode their embedded timestamp.
Enter the example value or paste your own input, choose the mode when one is available,...
Vertical Tank with Cone Bottom (gal, ft³)
Calculate volume of a vertical cylindrical tank with truncated cone bottom in gallons and cubic feet.
How to Calculate Vertical Cone-Bottom Tank Volume in Imperial...
Content-Type Header Checker
Paste response headers and check Content-Type, charset and nosniff against the expected response kind.
This checker is for debugging API responses, static assets and browser...
VO2 Max Estimator
Estimate your VO2 max in ml/kg/min from a resting heart rate, a Cooper 12-minute run or a 1.5-mile run test, then see your fitness...
Kettle Volume Calculator (mL, L)
Calculate the volume and water capacity of a kettle in milliliters and liters.
How to Calculate Kettle Volume
This calculator determines how much water a kettle...
Pixelate Image Online
Pixelate JPG, PNG, WEBP and AVIF images in your browser with block size control, preview and ZIP download.
How to use itAdd images and choose...
Paper Sheet Weight Calculator
Compute weight of paper sheets from GSM or US lb Bond and sheet count.
Work out how much a stack of paper weighs from its...
CSV Sorter
Sort CSV rows by a selected header or column number, with text or numeric ordering.
Enter the example value or paste your own input, choose...
Deck Stain Calculator
Estimate gallons of deck stain or sealer by floor area, railings, stairs, coats, and wood condition. Splits horizontal and vertical surfaces because their coat...
Feet to Yards Converter
Feet to yards converter using the exact 1 ft = 1/3 yd ratio. Covers fabric yardage, carpet runners, landscape fencing, and square or cubic...
Marketplace Seller Cashflow Calculator
Estimate the cash gap a seller may need to fund while costs are paid before marketplace payouts arrive.
Seller cashflow is a timing problem: inventory,...
Marketplace Storage Fee Estimator
Estimate marketplace storage fees in USD from unit count, cubic feet, storage days and your own monthly rate.
This estimator turns inventory volume into a...
Take-Home Pay Paycheck Calculator
Turn a salary or hourly rate into the net pay you actually take home each paycheck after tax, retirement and other deductions.
To get a...
File List to CSV Online
File List to CSV Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Grass Seed Calculator
Estimate pounds of grass seed and bag count by area, species, and new lawn vs overseed application — KBG, Tall Fescue, Bermuda, and seven...
Handmade Labor Rate Price Calculator
Calculate a handmade item price from labor hours, target hourly rate, materials, overhead, fees and margin.
Handmade pricing needs to pay for time as well...
Kubernetes HPA Calculator
Estimate Kubernetes HPA desired replicas from current replicas, target utilization and observed load.
This calculator applies the core Kubernetes Horizontal Pod Autoscaler replica formula to...
Hemisphere Volume Calculator (gal, ft³)
Calculate the volume of a hemisphere in gallons and cubic feet from its radius or diameter.
How to Calculate Hemisphere Volume in Imperial Units
Determine the...
Layer load from density and thickness calculator
Calculate kN/m², volume and total load from density in t/m³ and layer thickness.
Layer load from density and thickness
Calculate kN/m², volume and total load from...
Rate Limit Header Analyzer
Paste API response headers and interpret RateLimit or X-RateLimit budget, remaining requests and reset time.
This analyzer is for API debugging when a response includes...
kg to mL, L to kg and mL to kg Calculator
Convert kg, mL and liters using material density. Use kg to mL, kg to L, mL to kg or L to kg; choose water,...
Truncated Cone Volume Calculator (gal, ft³)
Calculate the volume of a truncated cone (frustum) in gallons and cubic feet.
How to Calculate Truncated Cone Volume in Imperial Units
Determine frustum volume in...
50/30/20 Budget Calculator
Split your monthly take-home pay into needs, wants and savings, then compare those targets with what you actually spend to see whether your budget...
PNG to PDF Converter
Convert PNG images to PDF locally in your browser with multiple files, transparency background, A4/Letter presets and margins.
How to use itAdd PNG files, choose...
Merge MP3 Online
Join several MP3 files into one in the browser with track order control, optional pause and local download.
How to use itAdd two or more...
CRC32 Checksum Calculator
Calculate a CRC32 checksum for text and show it as hex, decimal and signed 32-bit values.
Paste your value, choose the mode if the calculator...
Mixed Carton CBM Calculator
Calculate total CBM for mixed carton shipments from line quantities, carton dimensions and loading allowance.
Mixed shipments often contain several carton sizes, so one average...
Credit Card Payoff Calculator
Find out how many months it takes to clear your credit card balance and how much interest you will pay, then compare a fixed...
Add Watermark to Photo Online
Add a text watermark to JPG, PNG, WEBP and AVIF photos in the browser with position, size, opacity and ZIP download.
How to use itType...
JSON Schema Required Fields Checker
Paste a JSON Schema object and sample JSON to check required fields, basic types and enum values.
This checker is for quick API payload review...
km/h to m/s calculator
Convert km/h to m/s with a focused calculator, examples and visible formula.
Convert km/h to m/s with a focused calculator, examples and visible formula.The widget...
Square Millimeters Calculator
Compute area in mm² for 5 shapes, round-wire cross-section, and AWG ↔ mm² conversion.
Work out area in square millimetres for five shapes — rectangle,...
Signed Integer Range Calculator
Calculate minimum and maximum values for signed or unsigned integers by bit width.
Enter the example value or paste your own input, choose the mode...
Arctangent Calculator
Compute inverse tangent of any real number with result in degrees or radians.
This arctangent calculator returns the inverse tangent of any real number x,...
Hreflang Tag Audit Tool
Paste hreflang link tags or Link headers and check duplicates, self-reference, x-default notes and URL format.
Use this audit when international pages have copied hreflang...
HEX RGB HSL Color Converter
Convert a CSS color between HEX, RGB and HSL and preview the resulting swatch.
Paste your value, choose the mode if the calculator has one,...
Add Page Numbers to PDF
Add page numbers to a PDF in the browser with position, start number, text size and local saving.
How to use itAdd a PDF, choose...
Print-on-Demand Profit Calculator
Calculate print-on-demand profit in USD after production cost, shipping paid, fees, ads and return allowance.
Use this calculator to check print-on-demand economics before listing a...
Rotate Video Online
Rotate Video Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...
Waist-to-Height Ratio Calculator
Work out your waist-to-height ratio from a waist and height measurement, see which health category it falls into, and check the simple rule of...
Bucket Volume Calculator (mL, L)
Calculate the volume of a bucket in milliliters and liters from its dimensions.
How to Calculate Bucket Volume
This calculator finds the volume of a bucket...
Marketplace Repricing Floor Calculator
Calculate a marketplace repricing floor from product cost, fulfillment, selling fees, profit target and margin guardrails.
This calculator helps set the lowest price a repricing...
Horizontal Elliptic Tank Volume (m³, L)
Calculate volume and fill level of a horizontal tank with elliptical cross-section in liters and cubic meters.
How to Calculate Horizontal Elliptic Tank Volume
Compute volume...
Regex Escape Tool
Escape literal text so it can be safely used inside a JavaScript regular expression.
Paste your value, choose the mode if the calculator has one,...
Fuel Economy Converter
Enter a fuel-economy figure in one unit and instantly see it expressed in MPG (US), MPG (UK), litres per 100 km and kilometres per...
Sepia Photo Online
Make a sepia photo in the browser with soft, medium or strong intensity and local batch processing.
How to use itUpload photos, choose an intensity...
Add Watermark to PDF Online
Add a text watermark to PDF pages in the browser with opacity, placement, page ranges and local saving.
How to use itAdd a PDF and...
Marketplace Refund Reserve Calculator
Calculate a marketplace refund reserve in USD from sales, refund rate, refund lag, buffer and exception assumptions.
Use this reserve calculator to decide how much...
Roof Pitch Calculator
Convert between roof pitch X/12, degrees, percent slope, and roof-area multiplier with material suitability hints.
What pitch actually means
Roof pitch is a ratio between vertical...
Overlay Photo on Photo Online
Place one photo over another in the browser with scale, position, opacity, blend mode and ZIP download.
How to use itAdd at least two images....
Number Rounding Calculator: Decimals, Tens, Hundreds
Round any number to decimal places, tens, hundreds, thousands or other magnitudes with half-up, half-even, floor, ceiling or truncate.
Round any number to a chosen...
JSON Pointer Extractor
Extract a value from JSON using an RFC 6901 JSON Pointer path such as /items/0/name.
Enter the example value or paste your own input, choose...
Overtime Pay Calculator
Work out your gross pay when some hours are paid at an overtime premium, with a clear split of regular, overtime and double-time pay...
Rotate Image Online
Rotate JPG, PNG, WEBP and AVIF images in your browser with preview, batch processing and ZIP download.
How to use itAdd one or more images,...
CSV to Markdown Table Converter
Turn CSV or simple spreadsheet rows into a Markdown table for README files and docs.
Paste your value, choose the mode if the calculator has...
Bacon Cipher Converter
Encode text as Bacon A/B groups or decode five-symbol Bacon cipher groups back to letters.
This converter handles Bacon-style five-symbol groups for puzzle and teaching...
Remove Audio From Video Online
Remove Audio From Video Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
ROT13 and Caesar Cipher Tool
Apply ROT13 or a custom Caesar shift to letters while preserving punctuation and spacing.
Enter the example value or paste your own input, choose the...
HTML Heading Outline Checker
Paste HTML and review heading counts, skipped levels, empty headings and the visible outline.
This checker is for content QA after a CMS edit, template...
String Length Counter
Measure character count, line count, whitespace and byte length for any pasted string.
Paste your value, choose the mode if the calculator has one, and...
Binary to Text and Text to Binary Converter
Convert text to binary and binary back to text, with UTF-8 or ASCII encoding and selectable bit grouping.
Convert any text into its binary representation...
HTTP Request Header Size Calculator
Estimate request-header and cookie byte size from pasted HTTP headers to debug 400 or 431 responses.
This calculator helps debug oversized browser requests, especially when...
Remove Duplicate Lines Online
Remove Duplicate Lines Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Vertical Tank with Cone Bottom (m³, L)
Calculate volume of a vertical cylindrical tank with truncated cone bottom in liters and cubic meters.
How to Calculate Vertical Truncated Cone Bottom Tank Volume
Compute...
Ocean Freight W/M Calculator
Calculate ocean freight W/M chargeable units by comparing CBM, metric tons and minimum billing units.
Ocean LCL pricing often uses W/M, short for weight or...
Exponential Backoff Calculator
Build a retry schedule from base delay, multiplier, maximum delay and retry count.
Enter the example value or paste your own input, choose the mode...
Web App Manifest Validator
Paste manifest.json and check required PWA fields, display mode, start URL, scope and icon sizes.
This validator is for checking a web app manifest before...
CSV Pivot Table Generator
Create a simple pivot table from pasted CSV by grouping rows and aggregating a selected value field.
This browser-side pivot tool groups pasted CSV rows...
Energy & Power Converter
Convert between energy units (joule, kWh, BTU, calorie, therm, ft·lb, electronvolt) and power units (watt, kilowatt, horsepower, BTU/h) in one tool.
This converter handles two...
Logarithm Calculator
Compute log_b(x) for any base, solve for base or argument, work exponentials b^y, with change-of-base formula and reference table.
This logarithm calculator handles four tasks...
Cron Expression Checker
Check a five-field cron expression and preview the next scheduled run times.
Paste your value, choose the mode if the calculator has one, and use...
Password Entropy Calculator
Estimate password entropy from length and character set size without storing or sending the password.
Paste your value, choose the mode if the calculator has...
Race Finish Time Predictor
Predict your finish time for a target race distance from a recent race result, using the Riegel model, with predicted pace per km and...
Pressure Converter
Convert pressure units including kgf/cm² to kN/m², kPa to atm and bar to psi. Enter one value and the calculator shows Pa, kPa, MPa,...
Duotone Photo Online
Create a duotone photo locally in the browser with custom dark and light colors, effect strength and preview.
How to use itUpload photos, choose the...
Square Root Calculator
Calculate sqrt(x) with a decimal answer, simplified radical form and perfect-square checks.
Square Root CalculatorCalculate sqrt(x) with a decimal answer, simplified radical form and perfect-square...
WiFi QR Code Generator
Generate a WiFi QR payload and preview a QR code for WPA, WEP or open networks.
This generator builds a WiFi QR code payload from...
DMARC Alignment Simulator
Simulate DMARC pass or fail from Header From, SPF domain, DKIM domain and alignment modes.
This simulator checks whether SPF or DKIM would align with...
Loan Payoff Calculator
Find out when your loan will be paid off and how much interest you will pay, and see how much faster extra payments clear...
JavaScript Minifier
Lightly minify a JavaScript snippet by removing obvious comments and extra whitespace.
Enter the example value or paste your own input, choose the mode when...
Marketplace Subscription Fee Break-Even Calculator
Calculate how many marketplace orders are needed for a monthly subscription or account fee to break even.
This calculator compares a monthly seller subscription against...
Photo With Transparent Margins Online
Photo With Transparent Margins Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Pregnancy Due Date Calculator
Estimate your due date from LMP, conception date, ultrasound, or IVF transfer. Shows current gestational week, trimester, key milestones and a pregnancy timeline.
This pregnancy...
PDF to Text Online
Extract selectable text from PDF files in the browser and download a TXT file without OCR or server upload.
How to use itAdd a PDF,...
Barcode Generator
Generate a browser-side SVG barcode for CODE128, EAN-13, UPC, CODE39 and ITF formats.
This generator creates a barcode SVG from a value and selected barcode...
Steps to Distance Calculator
Convert a step count into distance in kilometres and miles. Estimate your step length from height, sex and gait, or enter a measured value,...
CSS Minifier
Minify a CSS snippet by removing comments, redundant spaces and optional semicolons.
Enter the example value or paste your own input, choose the mode when...
Parity Bit Calculator
Calculate an even or odd parity bit for a binary string and append it to the data bits.
Paste your value, choose the mode if...
Horizontal Oval Tank Volume (gal, ft³)
Calculate volume and fill level of a horizontal oval (stadium-shaped) tank in gallons and cubic feet.
How to Calculate Horizontal Oval Tank Volume in Imperial...
Mermaid Diagram Preview
Render Mermaid diagram text into an SVG preview and copy the generated SVG markup.
This preview tool renders Mermaid diagram syntax locally in the browser....
Handmade Product Pricing Calculator
Calculate a handmade product price in USD from materials, labor, overhead, fees and target profit margin.
Use this calculator to price a handmade item without...
Change Image Opacity Online
Change image opacity in the browser with percent control, transparent PNG/WEBP output, JPG background and batch processing.
How to use itAdd images and set the...
Emergency Fund Calculator
Work out how large your emergency fund should be, how many months of expenses you cover today, and either how long it takes to...
Scale Calculator
Convert between real and scaled lengths for drawings, maps and models. Find the ratio from two measurements. Rebase between scales.
A scale ratio relates a...
Steps to Calories Calculator
Estimate how many calories a step count burns from your body weight, walking pace and height, and compare the burn across common daily step...
Unicode Escape Converter
Convert text to JavaScript-style Unicode escape sequences and decode escapes back to text.
Paste your value, choose the mode if the calculator has one, and...
Sine Calculator
Calculate sin of any angle in degrees or radians with exact common values.
This sine calculator returns sin(θ) for any angle in degrees or radians,...
Body Surface Area Calculator
Calculate your body surface area in square metres from your weight and height, compare the four standard formulas side by side and see how...
Merge TXT Files Online
Merge TXT Files Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Vertical Conical Tank Volume (m³, L)
Calculate volume and fill level of a vertical tank with conical bottom in liters and cubic meters.
How to Calculate Vertical Conical Tank Volume
Compute volume...
Wok Volume Calculator (fl oz, gal)
Calculate the volume and capacity of a wok in fluid ounces and gallons.
How to Calculate Wok Volume in Imperial Units
Determine wok capacity in fluid...
Hemisphere Volume Calculator (m³, L)
Calculate the volume of a hemisphere in cubic meters and liters from its radius or diameter.
How to Calculate Hemisphere Volume
Compute the volume of a...
Image to PDF Converter
Create a PDF from images in your browser: JPG, PNG, WEBP and AVIF, multiple files, page presets, margins and one document.
How to use itAdd...
Marketplace Fulfillment Method Profit Calculator
Compare marketplace fulfillment, seller fulfillment and local pickup profit after fees, shipping, labor, storage and returns.
This calculator compares three fulfillment choices using the same...
SemVer Range Checker
Check whether package versions satisfy common SemVer ranges such as ^1.2.0, ~2.4.1, >=3.0.0 or 1.5.x.
This checker is for dependency updates, release notes and lockfile...
Function Graph Plotter
Plot a function graph from a formula, compare two functions, inspect intersections, export PNG and share a link.
What this graph plotter doesEnter a formula...
Pot Volume Calculator (fl oz, gal)
Calculate the volume and capacity of a cooking pot in fluid ounces and gallons.
How to Calculate Pot Volume in Imperial Units
Determine cooking pot capacity...
Hash Length Identifier
Inspect a hash-like string and list common algorithms that match its length and format.
Enter the example value or paste your own input, choose the...
Docker Compose Port Conflict Checker
Paste Docker Compose service text and find duplicate host-port mappings before local containers fail to start.
This checker is for local development Compose files where...
Add Shapes to PDF Online
Add Shapes to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Kettle Volume Calculator (fl oz, gal)
Calculate the volume and water capacity of a kettle in fluid ounces and gallons.
How to Calculate Kettle Volume in Imperial Units
Determine kettle water capacity...
Fence Calculator
Estimate fence posts, rails, pickets or panels, concrete bags for footings, and gate hardware for wood privacy, picket, vinyl, and chain link fences.
How post...
GraphQL Query Depth Calculator
Paste a GraphQL query and estimate maximum depth, field count, aliases, fragments and repeated fields.
This calculator is for a first-pass review of GraphQL query...
PNG to WEBP Online
Convert PNG to WEBP in the browser with batch processing, result quality control and ZIP download.
How to use itAdd PNG files, check WEBP quality...
Count Lines in Text Online
Count Lines in Text Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Concrete Calculator
Estimate concrete volume in cubic yards, 40/60/80 lb bag counts, and ready-mix truckloads for slabs, patios, driveways, and pads.
How the math works
Pouring a slab...
E-commerce Return Shipping Cost Calculator
Estimate return shipping cost per order from order volume, return rate, label cost, handling and recovery assumptions.
This calculator turns a return policy into a...
Truncated Cone Volume Calculator (m³, L)
Calculate the volume of a truncated cone (frustum) in cubic meters and liters.
How to Calculate Truncated Cone Volume
Compute the volume of a frustum (truncated...
Passphrase Generator
Generate a readable passphrase from a built-in word list and estimate its entropy.
Enter the example value or paste your own input, choose the mode...
Mixed Content HTML Checker
Paste HTML from an HTTPS page and find http:// assets, form actions, srcset entries and CSS URLs.
This checker is for the common deployment problem...
MPa to kgf/cm² calculator
Convert MPa to kgf/cm² with a focused calculator, examples and visible formula.
Convert MPa to kgf/cm² with a focused calculator, examples and visible formula.The widget...
Data Transfer Calculator
Compute transfer time, maximum file size or required bandwidth from file size and network speed, with decimal and binary units.
This tool converts between file...
Change Video Speed Online
Speed up or slow down MP4, MOV or WEBM locally in the browser with preview and exact percentage control.
How to use itAdd a video,...
Months of the Year
Reference of the 12 months with days, abbreviations, seasons, and quarters.
A reference widget for the 12 months of the Gregorian calendar. The interactive table...
Security Headers Checklist
Paste HTTP response headers and review HSTS, CSP, nosniff, referrer, permissions and frame controls.
This checklist turns pasted response headers into a compact review of...
DKIM Record Checker
Paste a DKIM TXT record and check selector name, version, key type, public key tag and obvious warnings.
This checker helps read a DKIM DNS...
Confidence Interval Calculator
Confidence Interval Calculator. Enter your own values first; presets below the fields are editable examples.
How to useEnter your own values first; presets below the...
XLSX to CSV Converter
Convert an uploaded XLSX workbook sheet to CSV or JSON locally in the browser.
This converter reads an XLSX workbook in the browser and exports...
Car Loan Calculator
Work out your monthly car payment from vehicle price, down payment, trade-in, interest rate and term, with sales tax, total interest and a full...
Torus Volume Calculator (gal, ft³)
Calculate the volume of a torus (donut shape) in gallons and cubic feet.
How to Calculate Torus Volume in Imperial Units
Determine torus volume using major...
User-Agent Parser
Parse a browser User-Agent string into likely browser, operating system and device class.
Enter the example value or paste your own input, choose the mode...
Creator Platform Payout Calculator
Estimate creator take-home payout after platform fees, payment processing, refunds, collaborator shares and reserves.
This calculator turns gross creator revenue into a practical payout estimate....
Debt Snowball Payoff Calculator
List your debts and a monthly budget to see your debt-free date and total interest with the snowball method, plus a side-by-side comparison against...
Regex Tester
Test a regular expression against sample text and list matches, indexes and capture groups.
Paste your value, choose the mode if the calculator has one,...
Topsoil Calculator
Estimate topsoil in cubic yards, bags, and tons for lawn topdressing, new lawn, raised beds, garden beds, and fill spots — with a 15%...
Basic Auth Header Generator
Generate an HTTP Basic Authorization header from a username and password locally.
Paste your value, choose the mode if the calculator has one, and use...
OGG to MP3 Online
Convert OGG audio to MP3 in the browser so the result opens in more players and apps.
How to use itAdd an OGG file, choose...
Blur Image Online
Blur JPG, PNG, WEBP and AVIF images in your browser with light, medium or strong blur and batch ZIP download.
How to use itAdd images...
Postman OpenAPI Coverage Checker
Paste OpenAPI JSON and a Postman collection to compare tested endpoints against documented operations.
This checker answers a practical API testing question: which documented endpoints...
MP4 to WEBM Online
MP4 to WEBM Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Cron Time Zone Converter
Preview upcoming five-field cron runs in one time zone and convert them to another time zone.
This converter previews upcoming cron run times from a...
Product Launch Break-Even Calculator
Estimate product launch break-even units from fixed launch costs, price, variable cost, ads, fees and returns.
This calculator estimates how many units a product launch...
IPv6 Compress and Expand Tool
Expand shortened IPv6 addresses and compress full IPv6 notation using the longest zero run.
Paste your value, choose the mode if the calculator has one,...
UUID Generator and Validator
Generate UUID v4 values or validate an existing UUID format, version and variant.
Paste your value, choose the mode if the calculator has one, and...
Image Srcset and Sizes Audit
Paste HTML and audit responsive image srcset, sizes, width descriptors, density descriptors and fallbacks.
This audit is for frontend and CMS QA when responsive images...
HEIC to JPG Converter
Convert HEIC/HEIF files to JPG in your browser with batch upload, presets and ZIP download.
How to use itDrop your HEIC/HEIF files into the upload...
Sod Calculator
Estimate sod by yard area: pallet count, roll count, and slab count with editable pallet coverage and 5 percent waste built in.
Pallet coverage is...
Horizontal Cylinder Tank Volume (m³, L)
Calculate the volume and fill level of a horizontal cylindrical tank in liters and cubic meters.
How to Calculate Horizontal Cylinder Tank Volume
Compute total and...
Online Video Editor
Edit short videos locally: add clips, reorder them, trim each card visually and export one MP4.
How to use itAdd several videos, move start/end handles...
ASCII Code Converter
Convert text to ASCII decimal, hexadecimal and binary codes, or decode code lists back to text.
Paste your value, choose the mode if the calculator...
MP3 to WAV Online
Convert MP3 to WAV locally in the browser: device-side decoding and uncompressed PCM WAV output.
How to use itAdd an MP3 file and process. The...
JSON to CSV Converter
Convert a JSON array of objects into CSV with quoted values and a selectable delimiter.
Paste your value, choose the mode if the calculator has...
HTTP Status Code Lookup
Look up common HTTP status codes and see their class, meaning and typical use.
Paste your value, choose the mode if the calculator has one,...
Volume Unit Converter
Convert between 24 volume units: mL, L, m3, cubic inches/feet/yards, US and UK fluid ounces, pints, quarts, gallons and barrels.
This converter handles 24 volume...
Ellipsoid Volume Calculator (gal, ft³)
Calculate the volume of an ellipsoid in gallons and cubic feet from its three semi-axes.
How to Calculate Ellipsoid Volume in Imperial Units
Determine the volume...
Package JSON Scripts Audit
Paste package.json and summarize scripts, dependency counts, engine fields and risky lifecycle script names.
This audit is for a quick read of a Node project...
Add Sticker to Photo Online
Add a text sticker or emoji to photos in the browser with position, size, rotation, opacity and ZIP download.
How to use itEnter a symbol...
Greater Than / Less Than Calculator
Compare two numbers, fractions, or decimals with the correct inequality symbol.
Compare any two values and see which is greater, smaller, or equal. Enter integers,...
Sharpen Photo Online
Increase photo sharpness in the browser with exact strength, preview, batch processing and ZIP download without server upload.
How to use itAdd photos and choose...
Slug Generator
Create a clean lowercase URL slug from a title or phrase and choose the separator.
Paste your value, choose the mode if the calculator has...
Meta Title and Description Preview
Draft a page title and meta description, preview the snippet and check length plus rough width.
This preview helps catch missing, vague or obviously truncated...
URL Query String Parser
Parse a URL query string into decoded key-value pairs and rebuild it after small edits.
Paste your value, choose the mode if the calculator has...
Image Alt Attribute Audit
Paste HTML and find images with missing, empty, repeated, long or file-name-like alt attributes.
This audit is for reviewing pasted HTML after an article, product...
Average Photo Color Online
Average Photo Color Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files,...
Centimeters to Pixels Converter
Convert centimeters to pixels at 72, 96, 150, or 300 DPI.
This converter turns a centimeter measurement into pixels using the chosen DPI (dots per...
Add Arrow to PDF Online
Add Arrow to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Seller Fee Sensitivity Calculator
See how seller profit changes when percentage fees move around the current rate while other costs stay fixed.
This calculator isolates the effect of seller...
Reorder PDF Pages Online
Change PDF page order in the browser with reverse order, custom sequences, thumbnails and a new local PDF.
How to use itAdd a PDF and...
Wok Volume Calculator (mL, L)
Calculate the volume and capacity of a wok in milliliters and liters.
How to Calculate Wok Volume
Determine the internal volume of a wok from its...
Simple Interest Calculator
Work out the simple interest on a fixed principal, or solve for the rate or time needed, and see how the result compares with...
Tip Calculator
Calculate tip, total and per-person share for any bill, any currency and any split.
Work out the tip amount, the final total and the per-person...
Chart Maker
Create pie, doughnut and polar area charts with labels, custom colors, JSON import/export and PNG/JPG download.
What you can createThis adapted chart maker builds pie,...
Add Margins to PDF Online
Add Margins to PDF Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Home Down Payment Calculator
Work out your home down payment, the loan amount left to finance and the estimated monthly mortgage payment, and check whether you reach the...
Square Footage Calculator: Rooms, Lots, L-shapes, Trapezoids
Add rectangles, triangles, circles, L-shapes, and trapezoids in one list. Subtract islands and obstacles. Forward the total to the paint, flooring, tile, drywall, sod,...
Robots.txt Rule Tester
Paste robots.txt rules, enter a user-agent and URL path, and see which wildcard, Allow or Disallow rule wins.
Use this when a crawl rule looks...
kN to Tonnes and t to kN — Force Converter
Convert kilonewtons (kN) to tonnes-force (t) and back using standard gravity 9.80665 m/s².
This calculator converts between kilonewtons (kN) and tonnes-force (t), using the standard...
Gray Code Converter
Convert binary to Gray code, Gray code back to binary, or decimal integers to Gray code.
Paste your value, choose the mode if the calculator...
Add Image to PDF Online
Insert JPG, PNG, WEBP or AVIF images into PDF pages in the browser with drag placement, millimeter coordinates and local saving.
How to use itAdd...
Millimeters to Pixels Converter
Convert millimeters to pixels at 72, 96, 150, or 300 DPI.
This converter turns millimeters into pixels using the formula px = mm / 25.4...
Compress Image to KB
Compress JPG, PNG, WEBP or AVIF images to a target size in KB directly in your browser.
How to use itAdd one or more images,...
DMS to Decimal Degrees Converter
Convert coordinates between degrees-minutes-seconds and decimal degrees both ways.
Convert geographic coordinates between degrees-minutes-seconds (DMS) and decimal degrees in either direction. Enter a DMS value...
Kubernetes Resource Quantity Converter
Convert Kubernetes CPU and memory quantities such as 250m, 1.5, 512Mi, 2Gi and 1000M into readable units.
This converter is for reading Kubernetes manifests, Helm...
Markup Calculator
Work out the selling price, markup, margin and profit from any two of cost, price and markup, and see exactly how markup percent and...
Unix Timestamp Converter
Convert Unix seconds or milliseconds to readable dates and convert dates back to Unix time.
Paste your value, choose the mode if the calculator has...
Cosine Calculator
Calculate cos of any angle in degrees or radians with exact common values.
Compute the cosine of any angle in degrees or radians to 8...
Photo on White Background Online
Photo on White Background Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the...
Shuffle Lines Online
Shuffle Lines Online works in the browser with local processing, preview and download. Files stay on your device.
How to use itAdd the files, choose...