Cube Root Calculator

About this calculator

The cube root of a number x is the value that, multiplied by itself three times, produces x; unlike a square root, a cube root is defined for negative numbers too, since a negative number multiplied by itself three times stays negative — the cube root of negative 8, for instance, is negative 2. This calculator computes cube roots for positive and negative real numbers alike, typically using an iterative numerical method that converges quickly to high precision.

Cube roots come up whenever a cubic relationship needs to be reversed: finding the side length of a cube from its known volume, working backward from a scaled-up or scaled-down volume in engineering and packaging design, and solving cubic equations in algebra classrooms all rely on this operation.

Enter any real number, positive or negative, and this calculator returns its cube root instantly and accurately.