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Circle Area

Calculate the area and circumference of a circle from its radius or diameter. Free circle calculator with the formula shown and instant results.

Results

Area

78.540

Formula Used

A = π * r^2

How this calculator works

Calculate the area and circumference of a circle from its radius or diameter. Free circle calculator with the formula shown and instant results.

Formula

A = π * r^2

Inputs

  • Radius

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