Circle Area Calculator
Calculate the area of a circle from its radius
About this calculator
The Circle Area Calculator helps you quickly determine the area of any circle by simply entering its radius. This tool is essential for students, engineers, architects, and anyone working with circular measurements in construction, design, or mathematical problems. It instantly applies the formula A = πr² to provide accurate results, saving time and eliminating calculation errors. Whether you're calculating floor space, garden areas, or solving geometry homework, this calculator streamlines the process.
How to use
Enter the radius of your circle in the input field using any unit of measurement (inches, feet, meters, etc.). Click the calculate button to instantly get the area result. The calculator will display the area in square units corresponding to your input measurement unit.
Frequently asked questions
What is the formula for circle area?
The formula is A = πr², where A is the area, π (pi) is approximately 3.14159, and r is the radius of the circle.
What if I only know the diameter?
Divide the diameter by 2 to get the radius, then use that value in the calculator for accurate area calculation.
What units should I use for the radius?
You can use any unit (inches, feet, meters, etc.). The area result will be in the corresponding square units.