Cube Root of 2 — cbrt(2) = cbrt2

The cube root of 2 is cbrt2. In decimal, cbrt(2) is approximately 1.259921 (irrational — the decimal never ends or repeats). This page shows the exact value, simplified radical form, decimal to 20 decimal places, step-by-step working, and a 3D cube visualisation....

2 = ?

CUBE ROOT OF 2

∛2

1.2599210499

Irrational — decimal never ends or repeats

Exact form

∛2

Decimal (6dp)

1.259921

Decimal (10dp)

1.2599210499

Is perfect cube?

No

(∛2)³

2 ✓

Between

1 and 2

DECIMAL PRECISION

21.2599210499

STEP-BY-STEP

1

Prime factorisation: 2 = 2

2

No perfect cube factor — ∛2 is already in simplest form

3

1³ = 1 < 2 < 8 = 2³ → ∛2 between 1 and 2

4

21.2599210499

FUN FACT

cbrt(2) approx 1.25992 is irrational. It appears in the ancient 'doubling the cube' problem — impossible with compass and straightedge alone.

NUMBER LINE (∛21.2599)

1

2

2

CUBE WITH VOLUME = 2

Vol=221.260

NEARBY PERFECT CUBES

0= 00³ = 0
1= 11³ = 1
8= 22³ = 8
27= 33³ = 27
64= 44³ = 64

CUBE ROOT LAWS

∛2 × ∛2 × ∛2= 2
(∛2)³= 2
∛(2 × 8)= 2∛2 ≈ 2.5198
∛(2 / 8)= ∛2/2 ≈ 0.6300
∛2 × ∛3≈ 1.8171
Created with❤️byeaglecalculator.com

HOW TO CALCULATE

  1. 1

    Find the prime factorisation of 2: 2 = 2. Look for any prime appearing 3+ times.

  2. 2

    No factor appears 3+ times, so cbrt(2) cannot be simplified and stays as cbrt(2).

  3. 3

    Locate cbrt(2) between integers: 1^3 = 1 < 2 < 8 = 2^3. So cbrt(2) is between 1 and 2.

  4. 4

    Decimal: cbrt(2) approximately 1.2599210499. Verify: (1.259921)^3 approximately 2.

WORKED EXAMPLE

cbrt(2): not a perfect cube. Factorisation: 2 = 2. Simplified: cbrt2. Decimal: cbrt(2) approximately 1.2599210499.

FREQUENTLY ASKED QUESTIONS

OTHER CUBE ROOTS

Bold bordered = perfect cubes (∛1=1, ∛8=2, ∛27=3)

RELATED CALCULATORS

MORE ALGEBRA CALCULATORS

Was this calculator helpful?

Last updated: April 28, 2026 · Verified by EagleCalculator team · Eagle-eyed accuracy for every calculation.