Cube Surface Area and Volume Calculator
This calculator works out the surface area, volume, face diagonal and space diagonal of a cube from a single measurement, the length of one side. A cube is a three-dimensional shape with six identical square faces, twelve equal edges and eight corners, so knowing just the side length lets you derive every other dimension using standard geometry formulas. Enter the side length and choose a unit, millimetres, centimetres, metres, kilometres, inches, feet or yards, and the calculator instantly returns the surface area, the combined area of all six faces, the volume, how much space the cube occupies, the face diagonal, the line running across one square face, and the space diagonal, the line running through the cube from one corner to the opposite corner. Full working is shown underneath, setting out each formula and the exact numbers used, so you can see how every figure was reached rather than just the final answer. This is useful for jobs such as working out how much material is needed to cover a cube-shaped object, checking how much a container will hold, or confirming whether a cube-shaped item will fit through a gap using its space diagonal. Results are calculated from exact geometric formulas and displayed rounded to three decimal places, so they stay accurate for whichever unit of length you choose to work in.
Cube Dimensions
About a Cube
A cube is a three-dimensional solid with six equal square faces, twelve equal edges, and eight vertices. All sides are equal length. It is a special case of a rectangular box (cuboid) where length = width = height = s.
Key formulas:
Surface area: SA = 6s²
Volume: V = s³
Face diagonal: d₁ = s√2
Space diagonal: d₃ = s√3