Ring or annulus area
Geometry / FREE CALCULATOR
Calculate the area between concentric circles.
Your answer starts here.
Enter your values and select Calculate to see the result and any available breakdown.
How to use this calculator
- Enter outer radius. Use the unit shown beside the field.
- Enter inner radius. Use the unit shown beside the field.
- Select Calculate and review the result. Select Reset to restore the example inputs.
How the calculation works
3.141592653589793*(Outer radius*Outer radius-Inner radius*Inner radius)
Worked example
Outer radius = 5; Inner radius = 3. Result: 50.2655 square units.
Understand your result
Calculate the area between concentric circles. The result is expressed in square units.
Assumptions and limitations
Outer radius must be at least inner radius. Results are rounded for display.
Questions about this tool
What does this tool calculate?
Calculate the area between concentric circles.
What should I check before using the answer?
Outer radius must be at least inner radius.
Related guides
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