Cube Size Calculator
Choose which measurement of the cube you know, side, volume, surface area, face diagonal or space diagonal, and enter it. The calculator works out all the others.
- Start from any value
- Volume and surface
- Both diagonals
Results use the same unit you enter. Volume is in that unit cubed.
A cube is set by one number: its side. Volume is the side cubed, surface area is six times the side squared, and the long diagonal from corner to corner is the side times 1.732. Know any one of these and you know them all.
Cube size chart
From the side. Search for a size.
| Side | Volume | Surface area | Space diagonal |
|---|---|---|---|
| 1 | 1 | 6 | 1.732 |
| 2 | 8 | 24 | 3.464 |
| 3 | 27 | 54 | 5.196 |
| 5 | 125 | 150 | 8.66 |
| 10 | 1000 | 600 | 17.32 |
| 20 | 8000 | 2400 | 34.64 |
A cube with 10 cm sides holds exactly one litre.
Side and volume
In centimetres. Slide the side.
The red line is the space diagonal, the longest straight line inside the cube.
How to work out a cube
From the side. Step through it.
Side
a.
To go back from volume to side, take the cube root. The cube root of 1,000 is 10.
Volume, surface or diagonal
Which to use. Compare them.
Space inside.
Area of all six faces.
Corner to far corner.
Surface area tells you how much paint, wrap or material covers the cube.
Before you build
Cube checks. Tick each item.
Tick each item as you go.
For a box made from sheet material, remember the material's thickness changes the inside size.
What you get
Every cube size. Each tile explains one result.
One edge.
Space inside.
All faces.
Across a face.
Through the middle.
Doubling the side multiplies surface area by 4 and volume by 8.
Frequently Asked Questions
No question matches that search.
How do I find the volume of a cube?
Multiply the side by itself three times.
How do I find the side from the volume?
Take the cube root of the volume.
What is the surface area of a cube?
Six times the side squared.
How long is a cube's diagonal?
The side times the square root of 3, about 1.732.
How many litres is a 10 cm cube?
Exactly one litre.
How many edges does a cube have?
Twelve, all the same length.
What is a cubic metre in litres?
1,000 litres.
One number, every measurement
Enter any one measurement and see the rest. It is the quickest way to size a box, a block or a storage cube.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.