Geometry & Trigonometry
Basic

Surface Area of a Sphere

The total surface area of a sphere.

Formula

A=4πr2A = 4\pi r^2

Variables

rRadius

Example

A sphere of radius 3: A = 4π·3² ≈ 113.1 square units.

Did You Know?

A sphere's surface area equals exactly four times the area of its own shadow (a great circle).

spheresurface area