# Cube surface area and net

Martin McBride

2021-02-11

- Categories:
- gcse
- geometry
- 3d geometry

Here is a cube of side $a$:

## Cube net

We find the net of a cube by unfolding it, like this:

This animation shows the cube being completely unfolded:

## Cube surface area

The surface area of the cube is the total area of all its faces. Assuming the side of the cube has length $a$, each face has an area of $a^2$:

Since there are 6 faces, the total surface area is:

$$ area = 6 a^2 $$