Cube Root Calculator
Find the cube root of any number, including negatives, and simplify roots like ∛54 = 3∛2.
About the Cube Root Calculator
Enter any number, including a negative one. The calculator gives the cube root to 25 significant digits, its simplest radical form and whether the number is a perfect cube.
The cube root of x is the number that, multiplied by itself three times, gives x. Unlike square roots, negative numbers have a real cube root: ∛−27 = −3.
The formula
∛(a³ × b) = a∛b
Perfect cubes
| n | n³ |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 27 |
| 4 | 64 |
| 5 | 125 |
| 6 | 216 |
| 7 | 343 |
| 8 | 512 |
| 9 | 729 |
| 10 | 1000 |
| 11 | 1331 |
| 12 | 1728 |
Worked example
∛54
- 54 = 27 × 2 = 3³ × 2
- ∛54 = 3∛2
- ≈ 3.7797631497
Questions people ask
What is the cube root of 1,000?
10, because 10 × 10 × 10 = 1,000.
Can I cube-root a negative number?
Yes: ∛−8 = −2.