Circle Area Calculator
Calculate area of a circle from its radius.
Circle Area Calculator
Calculate area of a circle from its radius.
Calculate circle area instantly from radius or diameter. Geometry made simple.
Key Features
Calculate area from radius
Calculate area from diameter
Calculate circumference
Show calculation steps
How to Use Circle Area Calculator
Enter Radius or Diameter
Input the circle radius or diameter
Calculate
Click calculate to find the area
View Results
See area, circumference, and diameter
Use Cases
Calculate circular area for landscapes
Engineering measurements
Cake and pizza sizing
Geometry education
Frequently Asked Questions
What is the formula for circle area?
Area = π × r² where r is the radius
What is pi?
Pi (π) is approximately 3.14159, the ratio of circumference to diameter.
How do I find radius from diameter?
Radius = Diameter / 2
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