Root calculator.
Use this free root calculator to get fast estimates, compare scenarios, and understand the numbers with clear step-by-step context.
Use the Root Calculator.
Results update automatically as you type. No account is required.
Enter your values
About the Root Calculator
A root calculator finds the nth root of a number — the value that, raised to the nth power, gives your number. Square roots (n = 2) and cube roots (n = 3) are the most common, but any degree works.
How it works
The nth root of x is x^(1/n). The square root undoes squaring; the cube root undoes cubing. Even roots of negative numbers are not real, while odd roots of negatives are negative.
Reading the result
The result is the root, with a verification that raising it back to the nth power returns your original number.
Note: Calculations run instantly in your browser and use exact mathematical formulas. For very large numbers, results are shown to standard floating-point precision.
FAQ
Why can’t I take the square root of a negative number?
Because no real number squared is negative. Even roots of negatives exist only as imaginary numbers, which this calculator does not cover.
What is the cube root of a negative number?
It is negative — for example, the cube root of −27 is −3, since (−3)³ = −27. Odd roots preserve the sign.
How does a root relate to an exponent?
A root is a fractional exponent: the nth root of x equals x raised to the power 1/n.