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Combinations and permutations calculator

Count selections, with or without order.

Your result

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How to use Combinations and permutations calculator
  1. Enter the values you want to calculate and choose the relevant units or settings.
  2. The result updates as you type. Adjust the available settings if needed.
  3. Review the result, then use Copy result or a download link when available.

Useful next steps

How to use it

Enter n distinct items and how many items r you select without replacement. Choose whether a different order should count as another result.

A worked example

Selecting 5 cards from 52 gives 2,598,960 combinations. Choosing an ordered sequence of 3 from 5 items gives 60 permutations.

What to know

Combinations use n! / (r! × (n-r)!). Permutations use n! / (n-r)!. The calculation uses exact integers for n up to 1,000. It does not model selection with replacement.