Root Calculator
Enter a number and the degree of the root you want.
This result is an estimate only. Double-check important figures before relying on them.
How it is calculated
- nth root of x = x^(1/n)
- For a negative x with an odd n, the root is negative
- The calculator checks whether the root is a whole number by raising it back to the power n
For raising to a power, use the exponent calculator.
Worked example
The cube root of 27:
- 27^(1/3) = 3, a perfect cube
The square root of 2 is 1.414214, which is not a whole number.
Why your number may differ
Roots are irrational for most numbers, so the answer is rounded to 6 decimal places.
Frequently asked questions
What is the nth root of a number?
The number that multiplied by itself n times gives the original. The cube root of 27 is 3 because 3 × 3 × 3 = 27.
Can I take the square root of a negative number?
Not in real numbers. Even roots of negative numbers need complex numbers. Odd roots, such as the cube root of −8 = −2, work fine.
How is it calculated?
The nth root of x is x raised to the power 1 ÷ n.