Circle Calculator

Radius, diameter, circumference and area from any one value.

Result

Radius5
Diameter10
Circumference31.415927
Area78.539816

Circle Calculator — FAQs

Circle formulas?

Area = πr², circumference = 2πr = πd. Diameter = 2×radius.

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Embed this Circle Calculator on your site

Free to use — paste this snippet into any webpage. It auto-resizes and includes a small attribution link. Add ?theme=dark to the iframe URL for dark mode.