ClarityKitFind a tool
Geometry

Annulus Area Calculator

Find the area between two concentric circles.

Use consistent dimensionsArea and volume units explained below
Geometry desk
Geometry desk

Match each dimension to the shape and keep units consistent.

See the method

Set the dimensions

Runs on your device

Your measurement

Your result

Let’s calculate.

Use the Calculate button to see your result.

Review the method below for assumptions and conventions.

How to use this tool

  1. Enter outer radius, inner radius.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

Input reference and sample values

Use the units and choices shown for each field. Sample values are provided for practice, not as recommendations.

InputFormat and unitsSample
Outer radiusNumeric value. Unit: m. Must be greater than zero.5
Inner radiusNumeric value. Unit: m. Zero or positive.3

Result for these sample inputs

50.2654825 m²

Select Try the example in the form to load these values and calculate them again. This replaces the current form inputs. Compare the result with the method and worked explanation below.

The method, explained

Area = π(outer radius² − inner radius²).

A WORKED EXAMPLE

Using outer radius = 5 m, inner radius = 3 m, the result is 50.2654825 m². Change these example inputs to match your task; use the method above to check each step.

What to keep in mind

Use the indicated units consistently. Ideal shapes are assumed; dimensions must describe the same object. Display rounding does not increase measurement precision.

Methodology maintained by ClarityKit. How these tools are built and checked.