Bit Mask Calculator

Build a bit mask from positions and show the result as binary, decimal and hexadecimal.

-Binary mask

-Hex mask

-Decimal

For beginners: how to read the result

Start with the first cardIt gives the direct answer for the current mode before the longer output text.

Use the output boxCopy the exact converted value, table, header or parsed data from the output area.

Keep sensitive data localThe calculator runs in your browser, but you should still avoid secrets that your policy forbids in tools.

Paste your value, choose the mode if the calculator has one, and use the first result card as the direct answer. The longer output area is designed for copying into code, documentation, API tests or a spreadsheet.

What the result means

Bit position 0 is the least significant bit. Ranges such as 5-7 include both ends.

What is not included

The calculator supports masks up to 64 bits and does not apply signed integer overflow.

Privacy note

The interactive calculation runs in your browser. The page still should not be used with passwords, tokens or personal data that your own rules do not allow in browser tools.