You would use this calculator to find cube root of a negative or a positive number. To use this calculator, enter the value for radicand $x$ and click Calculate button, The cubed root of a number is the number that would have to be multiplied by itself and by itself again to get the original number. However, the cube goes the other direction, e.g. the cube root of 64 is 4, as 4 multiplied by 4 multiplied by 4 is 64. The cube root of $x$ is $x$ raised to the $1/3$ power. Written as $√^3{x}=x^{1/3}$. For the negative number, the common definition of the cube root is that $$(-x)^{1/3} = -(x^{1/3})$$.