What this calculator does
A cube is a three-dimensional solid with six identical square faces and all edges equal in length. This calculator takes the edge length a and instantly returns the cube's volume V and total surface area S. Because the math is pure geometry, it works the same everywhere and with any consistent length unit you choose.
How to use it
Enter the edge length a in whatever unit you prefer (for example centimeters or meters), then read the results. Volume is reported in that unit cubed, and surface area in that unit squared. Just keep the unit consistent: if you type a in centimeters, the volume is in cubic centimeters and the surface area is in square centimeters.
The formulas explained
The volume is the space enclosed by the cube: $$V = a \times a \times a = a^{3}$$ The surface area is the total area of all the outside faces. A cube has 6 square faces and each face has area \(a^{2}\), so $$S = 6 \times a^{2}$$
Worked example
Suppose the edge length is \(a = 3\). Then the volume is $$V = 3^{3} = 27$$ and the surface area is $$S = 6 \times 3^{2} = 6 \times 9 = 54$$ For \(a = 2.5\), \(V = 2.5^{3} = 15.625\) and \(S = 6 \times 6.25 = 37.5\).
FAQ
What unit are the results in? Whatever unit you enter the edge in: volume comes out cubed and surface area squared. The formulas are unit-agnostic as long as you stay consistent.
Can the edge length be zero? Mathematically \(a = 0\) gives \(V = 0\) and \(S = 0\) (a degenerate cube). A negative edge length is not valid because length cannot be negative.
How is a cube different from a rectangular box? A cube is the special case where length, width, and height are all equal, so a single edge value fully describes it.
