Circle Calculator

Circle Calculator

Calculate circle diameter, circumference, and area.

Diameter

10

Circumference

31.4159

Area

78.5398

Formula

area = pi*r^2, circumference = 2*pi*r

Calculate circle diameter, circumference, and area.

How to Use

Calculate circle diameter, circumference, and area. Enter the Radius values and review the Diameter, Circumference, and Area outputs after you calculate.

  1. Open the calculator : Start with Circle Calculator.
  2. Enter values : Fill in the required inputs and any optional settings.
  3. Review the result : Read the output and use the about page for more detail if needed.

Common Questions

What formula does the Circle Calculator use?

Area = ?r?. Circumference = 2?r.

Which measurement matters most in the circle calculator?

The radius controls every result, and the diameter is just twice the radius.

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