Volume of a Sphere Calculator

A sphere is the set of all points the same distance from a centre — a perfectly round ball. That single distance, the radius, fixes everything about it: its diameter, its circumference, its surface area, and the space it encloses. The volume is that enclosed space, and it depends on the radius alone.

Three steps from a radius to a volume — and a fourth if you start from something else.

1. 1

   Get the radius

   If you have the diameter, halve it (r = d ⁄ 2). From a circumference use r = C ⁄ 2π; from a surface area use r = √(A ⁄ 4π).

   r = d ⁄ 2
2. 2

   Cube the radius

   Multiply the radius by itself three times. This is where the rapid growth comes from.

   r³ = r × r × r
3. 3

   Multiply by π

   Multiply the cubed radius by π, about 3.14159. Keep π symbolic for an exact answer, or use the decimal for a numeric one.

   π · r³
4. 4

   Multiply by four-thirds

   Scale that by 4⁄3 to finish. The number you get is the volume, in cubic units that match the radius.

   V = 4⁄3 · π · r³

The same sphere, reached four different ways. Each tab recovers the radius first, then applies one formula — and they all land on the same volume.

One formula that quietly sizes everything from storage tanks to planets.

Every measure of a sphere flows from the radius. Keep these together and you can move between any two of them.

A handful of facts that make sphere volume intuitive instead of a formula to memorise.

Almost every wrong answer comes from one of these three slips.

Common radii and diameters, with their volumes precomputed. Switch the dimension and the unit to match what you are searching for.

Common questions