Cube Root Calculator (∛n)

∛n with perfect-cube detection, simplified surd form, and decimal expansion.

Inputs

Result

∛n
4.000000
Perfect cube: ∛64 = 4.
  • n64
  • Decimal4.0000000000
  • Perfect cube?Yes
  • Simplified surd4
  • 262,144.000000

Step-by-step

  1. Decimal: ∛64 = 4.00000000.
  2. 64 is a perfect cube.

How to use this calculator

  • Enter any real number (positive or negative).
  • Read decimal + simplified surd.

About this calculator

The cube root of n is the value x where x³ = n. Unlike square roots, cube roots accept negative inputs (∛(−8) = −2). Perfect cubes: 1, 8, 27, 64, 125, …. Simplified surd: ∛54 = ∛(27 × 2) = 3∛2. JavaScript provides Math.cbrt which handles negatives correctly and runs fast on hardware. Useful in geometry (volume of a cube of size x = x³), finance (annualized growth from a 3-period total), and music (frequency ratios).

Frequently asked

Odd functions: y = x³ is one-to-one over all reals. (−2)³ = −8, so ∛(−8) = −2. Square root only defined for non-negatives in real domain.

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