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Switch tool with the current settings for diameter, and calculate circle area, circle radius, sphere volume or sphere surface area instead

## Related Tools

- Calculate diameter of circle from circumference
- Circle area calculator using diameter
- Circle radius calculator using diameter
- Length and distance converter
- Sphere volume calculator using diameter
- Sphere diameter to surface area calculator

## User Guide

This tool will calculate the circumference of a circle from the diameter, and will convert different measurement units for diameter and circumference.

### Formula

The formula used to calculate circle circumference is:

C = π · ø

#### Symbols

- C = Circle circumference
- π = Pi = 3.14159…
- ø = Circle diameter

### Diameter of Circle

Enter the diameter of a circle. The diameter of a circle is the length of a straight line drawn between two points on a circle where the line also passes through the centre of a circle, or any two points on the circle as long as they are exactly 180 degrees apart.

### Circumference of Circle

This is the total length of the edge around the circle with the specified diameter, if it was straightened out.