Math

Root Calculator

Use OmniCalc's root calculator to find square roots, cube roots, and higher-order roots instantly.

Root calculator

Find square roots, cube roots, and higher-order roots quickly.

Enter a value and root index to calculate the principal root instantly, with quick checks showing how the result behaves when raised back up.

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Why this result matters

What this calculator helps you answer

A direct algebra follow-on from quadratic, exponent, and scientific calculator pages. Use the tool above to enter a few clear inputs and get a practical answer you can use right away.

This root calculator helps students and everyday users calculate square roots, cube roots, and nth roots quickly. It also helps check whether a root is valid in the real numbers, making it useful for algebra practice and quick homework verification.

Formula and method

How the calculation works

The calculator finds the principal nth root by raising the value to the power of 1/n, while also checking whether the requested root stays valid in the real numbers.

Example

Example root calculation

If you enter value 81 and root index 4, the calculator returns 3.

FAQ

Common questions about this calculator.

Short answers to the questions people often ask before or after using the tool.

Question

What is the difference between a square root and an nth root?

A square root uses index 2, while an nth root lets you choose any root index such as 3 for cube roots or 4 for fourth roots.

Question

Why is an even root of a negative number invalid here?

Even roots of negative numbers are not real values, so this calculator marks them invalid instead of returning a misleading real-number result.

Question

What is the principal root?

The principal root is the main real root value returned for the chosen number and index when a real result exists.

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