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

## Related Tools

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

## User Guide

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

#### Formula

The formula used to calculate the circle radius is:

r = √(A / π)

###### Symbols

- r = Circle radius
- A = Circle area
- π = Pi = 3.14159…

#### Area of Circle

Enter the area contained within a circle.

#### Radius of Circle

This is the radius of a circle that corresponds to the specified area. The radius is the distance between the centre and any point on the outer edge of a circle.