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## Related Tools

- Calculate area of circle from diameter
- Circle circumference to diameter calculator
- Circle radius to diameter calculator
- Convert an area to different units
- Length and distance converter
- Sphere volume to diameter calculator
- Sphere surface area to diameter calculator

## User Guide

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

#### Formula

The formula used to calculate the circle diameter is:

ø = 2 · √(A / π)

###### Symbols

- ø = Circle diameter
- A = Circle area
- π = Pi = 3.14159…

#### Area of Circle

Enter the area contained within a circle.

#### Diameter of Circle

This is the diameter of a circle that corresponds to the specified area. 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.