Square Root Calculator
Calculate square roots and cube roots for valid real inputs.
Calculate a root
Enter a non-negative value and select a root index. The square root is the non-negative value whose square equals the input. A cube root can accept a negative value, while an even root of a negative real value is outside this page scope.
Root principle
The nth root of x is x raised to the power 1 divided by n. Check the index and radicand before calculating, especially when a worksheet uses a cube root or another index.
Worked example
The square root of 144 is 12. The cube root of 27 is 3. Keep the unit context in mind because the square root of an area has a length unit.
Frequently asked questions
Frequently Asked Questions About Online Calculators
Can I calculate a cube root?
Yes. Enter root index 3 and a valid real value.
Why is the square root of a negative number rejected?
This page focuses on real-number results.
Does it simplify every radical?
It calculates the numeric root; symbolic radical simplification may require a separate algebra workflow.