Area of Circle Formula

Area of Circle Formula

Formula

All Formulas

Summary

The area of a circle is given by the geometric constant (pi) multiplied by the radius of the circle squared.

Formula Terms
Expression Description
The area of the circle.
The geometric constant (pi), where
The radius of the circle.

How to use

To calculate the area of a circle, multiply the geometric constant (pi) by the radius of the circle squared. For example, the area of a circle with a radius of length is given by:

To calculate the area of the circle, substitute the value of into the formula, approximately , and evaluate the multiplication.

The area of a circle with radius length is approximately units squared.

Explanation

The area of the circle formula can be derived using calculus[1] or using a visual proof[2].

References

  1. Derive Area of Circle Formula
  2. Area of Circle Visual Proof