Circle Area Calculator
Enter the radius of any circle and instantly compute its area using the standard πr² formula. Ideal for geometry homework, engineering, and design projects.
Area
Enter values to calculate
How to Use the Circle Area Calculator
1
Enter the radius of the circle.
2
Click Calculate to compute the area.
3
View the result in square units.
Frequently Asked Questions
What formula is used to calculate circle area?
The area of a circle is calculated using A = πr², where r is the radius of the circle.
Can I use diameter instead of radius?
Enter half the diameter as the radius. The diameter divided by 2 equals the radius.
What units does the result use?
The result is in square units matching your input — if you enter centimeters, the area is in cm².