Cube Root Calculator

Calculate the cube root (∛) of any number. Supports positive and negative numbers.

Cube Root

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How to use the Cube Root Calculator

Enter any number (negative numbers are allowed).
Click Calculate.
See the cube root and whether the number is a perfect cube.
Use the square root calculator for square roots.

Formula used

∛x = y, where y × y × y = x

Worked example

Examples

∛27 = 3

∛100 ≈ 4.6416

∛(−64) = −4

Where cube roots are used

Cube roots turn a volume back into a length. A cube-shaped water tank holding 1,000 litres (1 m³) has sides of 1 m; one holding 8,000 litres has sides of 2 m, because ∛8 = 2. Unlike square roots, negative numbers have real cube roots, since a negative number multiplied three times stays negative.

Perfect cubes 1–10

1, 8, 27, 64, 125, 216, 343, 512, 729, 1000.

Tips for accurate results

The cube root of a number between 0 and 1 is larger than the number (∛0.125 = 0.5).
To check, cube the answer and compare.
x^1/3 in the scientific calculator gives the same result.

Frequently Asked Questions

Yes. For example ∛−8 = −2.

10.

Take the cube root of the volume.

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Content reviewed by Vinod, Easy Smart Calculator · Last updated October 2026

∛x = y where y³ = x