Area of a Circle Calculator

Calculate the area of a circle using its radius. The area of a circle is π × r², where r is the radius.

Input Parameters

Enter the radius of the circle

Calculation Results

Calculation Formula

Area = π × r²

Where:
π (pi) ≈ 3.14159
r = radius of the circle

The calculated area of the circle

Area of a Circle Calculator Usage Guide

Learn how to use the Area of a Circle Calculator and understand the mathematical principles behind it

How to Use This Calculator

  1. Enter the radius of the circle in the input field. The radius is the distance from the center of the circle to any point on its edge.
  2. Click the "Calculate" button to compute the area.
  3. The result will be displayed in the area field.
  4. If you want to start over, click the "Reset" button to clear all inputs.

Understanding the Formula

The area of a circle is calculated using the formula: Area = π × r²

  • π (pi) is a mathematical constant approximately equal to 3.14159. It represents the ratio of a circle's circumference to its diameter.
  • r is the radius of the circle.
  • The exponent ² means to multiply the radius by itself (radius squared).

Example

If a circle has a radius of 5 units:

Area = π × 5² = π × 25 ≈ 3.14159 × 25 ≈ 78.5398 square units

Applications

The area of a circle calculator can be used in various fields including:

  • Architecture and construction for designing circular structures
  • Engineering for calculating material requirements
  • Landscaping for planning circular gardens or patios
  • Art and design for creating circular patterns
  • Mathematics education for teaching geometry concepts