Sphere Calculator
Volume and surface area of a sphere from its radius.
How it works
Volume = 4/3 πr³; Surface = 4πr²
A sphere’s surface equals four times the area of a great circle of the same radius.
Worked example
Radius 3:
Volume 4/3 × π × 27 ≈ 113.10; surface area 4π × 9 ≈ 113.10.
The two coincide numerically at r = 3 — pure coincidence.
Notes and limitations
Volume scales with the cube of radius, area with the square. Double the radius: 8× volume, 4× area — which is why large objects shed heat less easily.