Circumference
This online calculator is a versatile tool for computing the properties of a circle. It allows you to find a circle's circumference from its radius, diameter, or area. Furthermore, it can perform reverse calculations, determining the radius, diameter, and area from a known circumference.
Formulas Used
- From Radius (r): C = 2 × π × r
- From Diameter (d): C = π × d
- From Area (A): C = 2 × √(π × A)
- From Circumference (C):
- Radius (r) = C / (2 × π)
- Diameter (d) = C / π
- Area (A) = C2 / (4 × π)
Practical Examples
- Known Radius: A circular garden has a radius of 5 meters. The calculator will find its circumference to be approximately 31.42 m.
- Known Diameter: A bicycle wheel has a diameter of 26 inches. The calculator determines its circumference is about 81.68 in.
- Known Area: A circular pizza has an area of 150 square inches. The calculator finds the length of its crust (circumference) to be roughly 43.41 in.
- Known Circumference: A running track has a circumference of 400 meters. The calculator will determine its radius is 63.66 m, diameter is 127.32 m, and area is 12,732.4 m2.
- Known Radius (small unit): A coin has a radius of 12 mm. Its circumference is calculated as 75.40 mm.
- Known Diameter (large unit): A circular field has a diameter of 0.5 miles. Its circumference is calculated as 1.57 mi.
- Known Area: A round table has a surface area of 2 square yards. Its circumference is approximately 5.01 yd.
- Known Circumference: The circumference of a pipe is 30 cm. Its calculated properties are: radius 4.77 cm, diameter 9.55 cm, and area 71.62 cm2.
- Known Radius (Imperial): A car tire has a radius of 1.2 feet. The calculator finds its circumference to be about 7.54 ft.
- Known Area (Metric): A circular pond has an area of 50 square meters. Its circumference is calculated as 25.07 m.
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