Circle Calculator

Free online circle calculator. Area, circumference, diameter from radius. Accurate and easy to use.

Radius

5.000000

r = 5

Diameter

10.000000

d = 2r = 2 × 5 = 10

Circumference

31.415927

C = 2πr = 2 × π × 5 = 31.4159265359

Area

78.539816

A = πr² = π × 5² = 78.53981633974999

Intermediate steps

d = 2 × 5 = 10

C = 2 × π × 5 = 31.4159265359

A = π × 5² = 78.53981633974999