Volume of a Cube Formula

Geometry Formulas: Area, Volume, Perimeter
Formula:

What is the formula for the volume of a cube?

Answer

Volume of a cube
V = a³

Here a is the side (or base). The result comes out in cubic units.

Where the formula comes from

V = a³

Fill the cube with unit cubes: a along each edge, so a · a · a of them. It is the rectangular prism with all three edges equal.

Worked examples

Let a = 4. Then the volume of a cube = 64 cubic units.

Let a = 2.5. Then the volume of a cube ≈ 15.63 cubic units.

The common mistake

Writing 3a instead of a³. Tripling an edge is not cubing it: for a = 4 the volume is 64, not 12.

Other quantities: Cube

See Also

Geometry Formulas: Area, Volume, Perimeter

These are the formulas for the area, perimeter, circumference, volume and surface area of the standard shapes — 31 of them. Each page shows not only the formula but where it comes from, what every letter stands for, two worked examples and the mistake that this particular shape invites. For example, it can help you find out what is the formula for the volume of a cube? (The answer is: V = a³). Pick the pair — "Area of a circle", for instance — and hit the "Find out" button.
Geometry Formulas: Area, Volume, Perimeter
Formula:

Values from the Formula

If a =Volume
11 cubic unit
28 cubic units
327 cubic units
464 cubic units
5125 cubic units
101,000 cubic units

FAQ

What is the formula for the volume of a cube?

Volume of a cube V = a³

Where does this formula come from?

Fill the cube with unit cubes: a along each edge, so a · a · a of them. It is the rectangular prism with all three edges equal.

What is the most common mistake here?

Writing 3a instead of a³. Tripling an edge is not cubing it: for a = 4 the volume is 64, not 12.

How do I use this formula?

Put your own numbers in place of the letters. With a = 2.5, for instance, the formula V = a³ gives ≈ 15.63 cubic units.