Geometry
Circle Area
Area enclosed by a circle.
Formula
Formula
A = π r2
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| r | radius | real number (ℝ) | — | input |
| A | area | computed result | — | result |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenradius r = 5
Result78.53981634
Example 2
Givenradius r = 1
Result3.141592654