Square Root & Exponent Calculator

Calculate X raised to the power of Y, or the square root, cube root, or any Nth root of a number — switch tabs for whichever one you need.

^
Works for negative, zero, and fractional exponents (5-2, 90.5, etc). A negative base only has a real result when the exponent is a whole number.
√
Odd roots (cube root, 5th root, etc.) of a negative number have a real answer — e.g. the cube root of -8 is -2. Even roots of a negative number don't.
Result Live
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Working with large exponents or powers of 10? Convert your result using our Scientific Notation Converter

Exponents

Formula
XY = X multiplied by itself Y times   Example: 210 = 1,024

Negative exponents flip the result into a fraction (2-3 = 1÷23 = 0.125), a zero exponent always gives 1 for any nonzero base, and fractional exponents (like 90.5) are the same thing as taking a root — 90.5 and the square root of 9 are the identical calculation, just written two different ways.

Roots

Formula
The N-th root of X is the number that, raised to the power of N, gives X   Example: the cube root of 27 is 3, since 33 = 27

Square root (N=2) and cube root (N=3) are the most common, but any whole-number root works the same way. A negative number's odd root has a normal, real answer — the cube root of -8 is exactly -2, since (-2)3 = -8. Its even roots don't: there's no real number that squares to a negative value, which is why the square root of a negative number is left undefined here rather than shown as an error-prone approximation.

A note on negative numbers with fractional exponents

Something like (-8)0.4 doesn't have a single, unambiguous real-number answer — unlike a clean N-th root (cube root, 5th root, etc.), an arbitrary decimal exponent on a negative base only resolves cleanly in complex numbers, which is outside what this calculator handles. It's rejected here rather than silently shown as a number that doesn't actually mean what it looks like it means.

Frequently asked questions

What is X to the power of Y?

X multiplied by itself Y times. 2 to the power of 10 is 2×2×2×2×2×2×2×2×2×2 = 1,024. Negative and fractional exponents work too — enter any base and exponent above.

Can you take the cube root of a negative number?

Yes — unlike square roots, odd roots (cube root, 5th root, etc.) of a negative number have a normal real answer. The cube root of -8 is -2, since -2 × -2 × -2 = -8.

Why can't you take the square root of a negative number?

Any real number squared is positive (or zero), so no real number can square to a negative value. The square root of a negative number is only defined in complex numbers, which this calculator doesn't cover.