Circle Calculator: All Values

Circle Calculator starts from one known value of a circle, its radius, diameter, area or circumference, and works out the rest. Choose the value you know, enter it with a unit, and the result shows the radius, diameter, circumference and area together.

What you get
• Four starting values: radius, diameter, area or circumference
• Units from meters and centimeters to miles, yards, feet and inches
• Circumference and area shown with π and as a decimal
• Radius, diameter, circumference and area in one result

Where it helps
• Sizing a round table, pizza, pond or garden bed
• Finding the diameter of a pipe from its circumference
• Working out the area of a round rug or lid
• Checking geometry homework about circles

Made for daily use
• Light and dark theme
• 28 languages, with right-to-left layout where it belongs

Part of Calculator.io
Circle Calculator runs on the Calculator.io calculator engine. The More calculators link opens the full Calculator.io app, with 170+ tools for math, money, health and dates.