Circle Calculator

Find a circle's radius, diameter, area, and circumference from one known value.

Area

78.53981634

31.41592654 circumference

Radius5

Diameter10

Circumference31.41592654

Area78.53981634

About the Circle Calculator

Find a circle's radius, diameter, area, and circumference from one known value.

It runs entirely in your browser — nothing you type is sent to a server — and the result updates as you edit the inputs. Estimates are for educational and informational purposes only; see ourdisclaimer.

Common searches

pi
circumference
circle area

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