Permutation and Combination Calculator

nPr and nCr, plus permutations with repetition and multinomial coefficients.

Calculator Numbers & Math Updated Apr 20, 2026
How to Use
  1. Enter n (total) and r (chosen).
  2. BigInt arithmetic handles n up to 170+.
Input
Presets
Results

Show Work

Enter values to see the step-by-step calculation.

Formulas

Permutations
nPr = n! / (n − r)!
Combinations
nCr = n! / (r! · (n − r)!)
With repetition
permutation = n^r · combination = C(n+r−1, r)

About the Permutation and Combination Calculator

Working on everyday maths and number work? The Permutation and Combination Calculator is a free browser tool that gives you the answer in seconds. nPr and nCr, plus permutations with repetition and multinomial coefficients.

How it works

Put each value in its box and read the answer as you go. Because it recalculates live, you can play with the inputs to see how each one moves the result — handy for checking your own working or planning ahead. Everything happens on your device, so it is fast and private.

Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.

Frequently Asked Questions

How do I use the Permutation and Combination Calculator?

Simply type your numbers and read the result, which refreshes the instant you change something. There is nothing to submit and nothing to wait for.

Do I need to install or sign up for anything?

Not at all — it runs in the browser with nothing to install and no account. After it loads once, it even works without an internet connection.

Is my information private?

Yes. Everything happens in your browser. Nothing you type is sent to a server or saved anywhere.

Common Use Cases

Get an answer fast

Type what you have and get the answer in seconds — on a phone, tablet, or computer.

Try different numbers

Change one thing and watch the answer change. It is an easy way to compare your choices.

Nothing to set up

Open the page and start. There is nothing to install, and no account to make.

No data leaves your browser

The tool runs locally, so whatever you enter stays with you and only you.

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