Power Calculators

🧊 Perfect Cube Checker

Check whether a number is a perfect cube and calculate its nearest integer cube root.

No ratings yet — be the first
Rate it: ★ ★ ★ ★ ★

Enter details

Fill in the details and click Calculate to see your results.


Also available in our Android app, with charts and full breakdown tables.

📘 About the Perfect Cube

This calculator tests whether the entered value is a perfect cube.

The cube root is evaluated numerically and the reconstructed cube is used as the check.

🧮 Formula

Cube root
r = ∛n
Perfect cube test
r³ = n

Where

  • n = input
  • r = cube root of n
  • n is a perfect cube when r³ = n
Use integer inputs for an exact perfect-cube check.

✏️ Worked example

Is 125 a perfect cube?

You enter
Number125
You get
Perfect Cube0
Cube Root Estimate5
Reconstructed Cube125

Yes. 5³ = 125.

Try this example →

🧭 How to use this calculator

What you enter

  • Number

What you get

  • Perfect Cube
  • Cube Root Estimate
  • Reconstructed Cube

💡 Examples

  • 8 is a perfect cube because 2³ = 8.
  • 27 is a perfect cube because 3³ = 27.
  • 100 is not a perfect cube.

❓ Frequently asked questions

What is a perfect cube?

It is an integer equal to another integer cubed.

Can negative perfect cubes exist?

Yes. For example, -8 = (-2)³.

Should I enter a whole number?

Yes, for the intended exact classification.