Square Root Calculator

Calculate the square root, cube root, or any nth root of a number. Includes a perfect squares reference table.

Calculate Root

2

Perfect Squares Reference (1–20)

11
24
39
416
525
636
749
864
981
10100
11121
12144
13169
14196
15225
16256
17289
18324
19361
20400

Square Roots & nth Roots

Square Root (√x) — The number that, when multiplied by itself, equals x. Example: √144 = 12 because 12² = 144.

Cube Root (∛x) — The number that, when cubed, equals x. Example: ∛27 = 3 because 3³ = 27.

nth Root (ⁿ√x) — The number that, when raised to the power n, equals x. Calculated as x^(1/n).

Perfect Squares — Numbers whose square root is a whole integer (e.g. 1, 4, 9, 16, 25 …).

Negative numbers: Even-order roots (2nd, 4th…) of negative numbers are not real. Odd-order roots (3rd, 5th…) of negative numbers are negative real numbers.

Frequently Asked Questions

The square root of a number x is the value that, when multiplied by itself, gives x. For example, √49 = 7 because 7 × 7 = 49.

The nth root of x is x raised to the power of 1/n. For example, the 4th root of 81 = 81^(1/4) = 3.

Not in real numbers. The square root of a negative number is an imaginary number (e.g. √−1 = i). However, odd roots of negative numbers are real — for example, ∛−8 = −2.

A perfect square is an integer whose square root is also an integer. Examples: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100.

Related Tools