Root Calculator – Find Square, Cube and Nth Roots
Calculate the nth root of a number.
About the Root Calculator
What is the Root Calculator?
A root calculator computes the nth root of a number — the value which, multiplied by itself n times, gives the original number.
Why use this calculator?
Square roots calculate areas, cube roots volumes, and general roots appear all through finance, geometry and science.
How to use it
- Enter the number.
- Enter the root degree: 2 for square, 3 for cube, etc.
- Read the result plus a verification row.
Formula
nth root of x = x^(1/n).
Even roots of negative numbers have no real answer, which the calculator reports clearly.
Frequently Asked Questions
Why is the square root of 2 irrational?
It cannot be written as a ratio of integers — a famous proof by contradiction shows no fraction squares to exactly 2.
Can I root a negative number?
Yes for odd roots (cube root of −8 is −2) but not for even roots in the real numbers.
What order of operations does this use?
It follows standard PEMDAS/BODMAS rules: parentheses, exponents, multiplication and division, then addition and subtraction.
How precise are the answers?
The calculator uses double-precision floating-point math (about 15 significant digits) and rounds the display. For exact symbolic results use dedicated algebra software.
Can I enter negative numbers or decimals?
Yes. Negative values, decimals and very large or small numbers are all supported unless a field says otherwise.
What does it mean if I get an error?
Errors usually mean an invalid input, such as division by zero or a negative value where only positives make sense. Check your entries and try again.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.
How accurate are the results?
We use standard, widely accepted formulas and calculate in your browser using double-precision arithmetic. Results are rounded for readability, so treat them as reliable estimates rather than a guarantee. Real-world factors can vary the true figure.
Can I add this calculator to my own website?
Yes. Open this calculator page and use the "Add to your website" box in the sidebar to copy a ready-made iframe snippet, then paste it into any HTML page.
Does it work on a phone or tablet?
Yes. The layout is fully responsive, so it works on desktops, laptops, tablets and mobile phones, and every input adapts to touch screens.