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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
- Calculate radius of circle from area
- Circle radius to circumference calculator
- Circle radius to diameter calculator
- Convert an area to different units
- Length and distance converter
- Sphere radius to volume calculator
- Sphere radius to surface area calculator
This tool will calculate the area of a circle from the radius, and will convert different measurement units for radius and area.
The formula used to calculate circle area is:
A = π x r2
- A = Circle area
- π = Pi = 3.14159…
- r = Circle radius
Radius of Circle
Enter the radius of a circle. The radius is the distance between the centre and any point on the outer edge of a circle.
Area of Circle
This is the area contained within a circle with the specified radius.