Circumference Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
100% FreeRuns in your browserBasic
Enter Values
Enter your values and press Calculate to see results.
How to use this calculator
- Enter the radius.
- Press Calculate for the circumference, diameter and area.
How it works
The circumference of a circle is 2 × π × radius. The diameter is 2 × radius, and the area is π × radius².
Worked example
Radius 1 m. Circumference = 2 × π × 1 = 6.2832 m.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.