Do I need to sign up?

No. The tool works without an account.

Are my data uploaded?

Compatible operations run locally in the browser.

Circumference = 2 × π × radius, or π × diameter.

Circumference is in the same linear units as the radius or diameter (e.g., cm if radius in cm).

Calculate the circumference of a circle from its radius or diameter using C = 2πr or C = πd.

Circle circumference

6.2832

Radius

Examples

Radius 1 → 6.2832

Radius 2 → 12.5664

Loading tool…

Recommended next step

After using Circle Circumference Calculator, continue with Acceleration Calculator.

Tools selected to complete the same task.

4 steps

Tool guide

Practical information to understand the result and use this tool correctly.

Calculate the circumference of a circle from its radius or diameter using C = 2πr or C = πd.

The tool runs directly in the browser for immediate results.

Do I need to sign up?: No. The tool works without an account.
Are my data uploaded?: Compatible operations run locally in the browser.
What is the formula?: Circumference = 2 × π × radius, or π × diameter.
Units?: Circumference is in the same linear units as the radius or diameter (e.g., cm if radius in cm).