Circle Calculator

Enter the **radius** or **diameter** of a circle to calculate the **area**, **circumference**, **diameter**, and **radius**.

Radius Diameter

Radius:

Diameter:

Circumference:

Area:

Related Tools

Triangle Calculator Square Area Calculator Cylinder Volume Calculator Sphere Calculator

Circle Calculator - Comprehensive Guide

A **Circle Calculator** is a mathematical tool designed to help users quickly find important properties of a circle, such as:

• Radius (r): The distance from the center of the circle to its edge.
• Diameter (d): Twice the radius, or the longest straight line passing through the center of the circle.
• Circumference (C): The perimeter or total distance around the circle, calculated as **C = 2πr**.
• Area (A): The total space inside the circle, calculated as **A = πr²**.

How to Use the Circle Calculator?

Simply enter the **radius** or **diameter** into the input field and select the correct unit. The calculator will instantly compute the missing values.

Real-Life Applications of Circle Calculations

Circle calculations are commonly used in **architecture, engineering, physics, and everyday tasks** such as:

• Measuring **wheels, gears, and round objects**.
• Calculating the **area of circular gardens, pools, or pipes**.
• Determining **circular motion** in physics.

Formula Reference

✔ **Circumference**: \( C = 2πr \) or \( C = πd \)

✔ **Area**: \( A = πr² \)

✔ **Diameter**: \( d = 2r \)

✔ **Radius**: \( r = d ÷ 2 \)

Our **Circle Calculator** simplifies these computations, making it a must-have tool for **students, engineers, and DIY enthusiasts**.