Circle Calculator
Know one measurement of a circle and you can work out the rest. Enter the radius, diameter, circumference or area.
Type a number and the answer appears straight away.
Your answer
Area78.5398
- Radius
- 5
- Diameter
- 10
- Circumference
- 31.4159
The math behind it: Circle Calculator
area = πr² circumference = 2πr diameter = 2r
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