Find circle area and circumference from the radius.
Free · Private · Runs in your browser
Math tool
Circle Area Calculator
Find circle area and circumference from the radius.
Your result will appear here after you submit valid inputs.
Formula and method
This calculator applies area = πr² to the values you enter. Calculations happen locally in your browser, and the displayed result is not a quote, diagnosis, or professional recommendation.
Boundaries
All values are entered directly in the browser.
The result is shown without intermediate display rounding.
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