Square root
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Use this free root calculator to find square roots, cube roots, and nth roots with real-number guardrails, exponent form, power checks, examples, and steps.
Find square roots and cube roots for math, science, and study problems.
Calculate nth roots such as fourth roots or fifth roots.
Convert root notation into rational exponent form.
Check whether a negative radicand has a real-number root.
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-5
3
Need a slower walkthrough, a related calculator, or the full library? These links keep you close to the task you started.
Quick answers about square roots, cube roots, nth roots, negative radicands, exponent form, and privacy.
An nth root asks what number raised to the nth power gives the radicand. For example, the cube root of 125 is 5 because 5^3 = 125.
A square root uses index 2, so the answer squared returns the radicand. A cube root uses index 3, so the answer cubed returns the radicand.
The main inputs are the numbers, operation, mode, or known values the calculator needs. Keep units consistent, enter percentages the way the page label shows, and use the examples as a quick check before trusting the answer.
Read the headline answer, then check the supporting lines and examples to understand how the calculator got there. If one input changes, rerun the tool and compare the new answer instead of guessing.
Check units, signs, rounding, and the selected mode before copying the answer. If the number feels weird, rerun one of the examples first, then put your own values back in slowly.
It can calculate real odd roots of negative numbers, such as root_3(-125) = -5. Even roots of negative numbers are not real numbers, so the calculator shows an error.
A root can be rewritten as a rational exponent. The nth root of x is the same as x^(1/n).
No. This calculator uses whole-number root indexes, such as 2, 3, 4, or 5.
Yes. Recent root answers stay only in the current browser tab while you use the page. They are not sent to a server.