This cube root calculator instantly finds the cube root of any number. Enter a value and see the result update in real time, with a handy indicator when you've found a perfect cube.
Cube root calculator
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What is a cube root?
The cube root of a number is the value that, when multiplied by itself three times, equals the original number. Written as ∛x or x^(1/3).
For example: ∛27 = 3, because 3 × 3 × 3 = 27.
Unlike square roots, cube roots work for negative numbers too. The cube root of -8 is -2, since (-2) × (-2) × (-2) = -8. Cube root is the inverse of cubing a number.
Perfect cubes
A perfect cube is a number whose cube root is a whole number. The calculator shows a "Perfect Root" badge when you enter one. The first few perfect cubes are:
- 1 (1³)
- 8 (2³)
- 27 (3³)
- 64 (4³)
- 125 (5³)
- 216 (6³)
- 343 (7³)
- 512 (8³)
- 729 (9³)
- 1000 (10³)
