Circle & Sphere Calculator
Calculate area, circumference, volume, and surface area for circles and spheres. Compute from either radius or diameter.
Input value
Formulas
Area = πr²
Circumference = 2πr
Diameter = 2r
How to Use
Enter Radius
Enter radius or diameter
Calculate
Area, circumference, volume calculated automatically
View Result
Check all calculation results
Features
Circle & Sphere
Show both 2D (circle) and 3D (sphere) calculations
Reverse Calculation
Reverse-calculate radius from area or circumference
Sector Support
Also calculate sector area and arc length
FAQ
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