What you provide
What you provide
- Outer radius expressed in units, using the same scenario as the other inputs
- Inner radius expressed in units, using the same scenario as the other inputs
MATH / PLANE GEOMETRY
Annulus Area Calculator
Calculate the area and radial width of a circular ring. Inspect the equation, substituted values, result, assumptions, and interpretation in one guided workspace.
- 01 Calculated in this tab
- 02 Values stay in this browser tab
- 03 Use boundary
Use boundary
Calculation path
Calculate the area and radial width of a circular ring. The page evaluates the displayed equation from your supplied values and presents both symbolic and substituted KaTeX working so the arithmetic can be checked.
Calculation path
A=pi(R^2-r^2)
What you receive
What you receive
- Annulus area in square units from the stated equation
- A symbolic formula plus substituted working with your values
- Visible assumptions, field guidance, and an authoritative learning reference
Use boundary
Choose the maximum decimal places shown. This does not increase source accuracy.
Circles are concentric and the inner radius does not exceed the outer radius.
Use internally consistent units and retain extra precision when carrying the result into another calculation.
Reviewed reference factors