Circle Calculator
Circle Calculator
This tool calculates all properties of a circle (Area, Circumference, Diameter) from any single known value.
[Image of a circle diagram with radius, diameter, circumference]What is a Circle?
A circle is a shape consisting of all points in a plane that are a given distance from a given point, the center. The key properties of a circle are:
- Radius (r): The distance from the center to any point on the circle.
- Diameter (d): The distance across the circle passing through the center. It is twice the radius (d = 2r).
- Circumference (C): The total distance (perimeter) around the circle. It is calculated as C = 2πr.
- Area (A): The space enclosed by the circle. It is calculated as A = πr².
Enter any one value:
How to Use This Calculator
It’s very simple:
- Enter any one known value (Radius, Diameter, Circumference, or Area).
- Leave all other fields blank.
- Click the “Calculate” button.
- The calculator will automatically find all other properties and fill in the empty fields.
- Click “Reset” to clear all fields for a new calculation.