How does the Circle Calculator work?

Calculate circle area, circumference, and diameter. The tool calculates an estimate from the values entered.

Can I copy the result?

Yes. Use the Copy Result button to copy the current results.

Geometry

Calculate circle area, circumference, and diameter.

Primary Result -

Secondary Result -

Additional Result -

Formula

Area = pi*r^2; Circumference = 2*pi*r

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