Python 3.11+Numbers & mathfunction

math.cbrt

roots/powers

The cube root of a number (3.11+).

Syntax

math.cbrt(...)

The reason to prefer it over exponentiation: cbrt takes the root of negative numbers directly, while (-8) ** (1/3) yields a complex number in Python 3 and math.pow(-8, 1/3) raises ValueError outright. The result is always a float and may miss an exact integer by a last-digit rounding step, so compare with math.isclose() rather than ==.

Examples

import math
print(round(math.cbrt(27), 4))   # → 3.0
print(round(math.cbrt(-8), 4))   # → -2.0
print(round(math.cbrt(0.001), 4))   # → 0.1
print(math.cbrt(0))   # → 0.0
print(math.pow(-8, 1 / 3))   # → ValueError

See also

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