Online calculators

Our site contains more than 100 free online calculators on math, geometry and physics.

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Calculating the perimeter of the circle online

Our online calculator allows you calculate the perimeter of a circle in two ways: through its diameter or through its radius. To find the perimeter of a circle to select the appropriate method, enter the length of the diameter or radius and click “To calculate”, the calculator will give an answer and a detailed solution!

Enter the data for the calculation of the perimeter
Select the method of calculating the perimeter:
The formula through the radius:
r =
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