Cube Surface Area Calculator
Six identical square faces — enter one edge for the total surface area, along with the volume and the area of a single face.
A cube has six square faces, each of area a², so the total is 6a².
How the cube surface area calculator works
A cube has six square faces, each of area a², so the total is 6a². Doubling the edge quadruples the surface area but multiplies the volume by eight, which is why large cubes have proportionally far less surface than small ones.
Formula: cube 6a²; box 2(lw+lh+wh); sphere 4πr²; cylinder 2πr(r+h); cone πr(r+l); pyramid a² + 2a·s
Worked examples
| Inputs | Total surface area | Note |
|---|---|---|
| Edge 3 | 54 | six faces of 9 — total 54 |
| Edge 10 | 600 | 600 — and a volume of 1,000 |
| Edge 2.5 | 37.5 | 37.5 |
FAQFrequently asked questions
What is the surface area of a cube?
Six times the side squared: 6a². For a 3 cm cube that is 6 × 9 = 54 cm².
How is it different from volume?
Volume is a³, the space inside. Surface area is the wrapping — they grow at different rates.
What if my box is not a cube?
Use the box surface area page, which takes a different length, width and height.
How much paint or paper do I need?
The total surface area, plus an allowance for overlap and waste — usually 10%.
Why do small cubes have more surface for their size?
Because area grows with the square of the edge while volume grows with the cube, so the ratio falls as things get bigger.
Where these figures come from
- NIST Digital Library of Mathematical Functions — reference definitions for elementary and special functions
- Wolfram MathWorld — definitions and formulas for every topic on this page
- NIST/SEMATECH e-Handbook of Statistical Methods — the statistical formulas (mean, variance, z, confidence intervals, sample size)
- Australian Curriculum (ACARA) — Mathematics — the terms and methods taught in Australian schools
Last checked: September 2026. Formulas are fixed by mathematics and do not change with tax years or regulations.