Sphere surface area calculator
Find the outside area of a sphere from its radius. The result is in square centimeters.
Formula
A = 4πr².
Radius r: 3 cm · Surface area ≈ 4×pi×(3 cm × 0.01 m/cm)^2×10000
How to use
- Enter the sphere's radius.
- Choose the length unit.
- Read the surface area in cm².
Examples
- A sphere of radius 3 cm has surface area 36π ≈113.097336 cm².
Frequently asked questions
Should I enter radius or diameter?
Enter radius, which is half the diameter.
Is this the area of a circle?
No. A sphere's surface area is four times the area of a circle with the same radius.
What happens if I double the radius?
The surface area becomes four times as large.
Sources
Updated: