Root Calculator
Find the square, cube or any nth root of a number.
How to use
- 1 Enter the number you want the root of (the radicand).
- 2 Enter the root degree: 2 for square root, 3 for cube root, and so on.
- 3 Read the result and the radical expression below.
- 4 Copy the value to reuse it elsewhere.
About Root Calculator
The Root Calculator finds the nth root of a number — the value that, raised to the given power, returns your original number.
Enter the number you want to take the root of (the radicand) and the degree of the root: 2 gives the square root, 3 the cube root, 4 the fourth root, and so on.
The calculator evaluates the result instantly and shows it alongside a readable radical expression so you can copy either the plain value or the full statement.
Roots are full of edge cases that other calculators handle silently, leaving you staring at NaN.
This one is explicit about them.
A negative number has a real root only when the degree is an odd whole number — the cube root of -27 is -3, but the square root of -4 has no real answer — so the tool returns that value where it exists and a calm explanation where it does not.
A zero degree is rejected because a 0th root is undefined, and any result that drifts into floating-point noise (like the cube root of 64 coming back as 3.9999…) is snapped to its clean value.
Everything runs locally in your browser, so nothing you type is uploaded, and the tool keeps working offline once the page has loaded.
It is handy for geometry, statistics, growth-rate problems and anywhere you need to reverse an exponent.
FAQ
Can I take the root of a negative number?
Only when the degree is an odd whole number. The cube root of -27 is -3, but a negative number has no real square root, so the calculator explains that instead of showing NaN.
What degree gives the square root?
A degree of 2. The square root is just the 2nd root; the cube root is the 3rd root; the calculator works for any whole or decimal degree except zero.
Why does the cube root of 64 show as exactly 4?
Floating-point math returns 3.9999999999999996; the calculator rounds away that tiny error so clean roots read as the whole numbers you expect.