Permutation and Combination Calculator

Permutation and Combination Calculator

Permutations and Combinations Explained

In mathematics, permutations and combinations are two different ways of grouping items from a larger set. Both are fundamental concepts in combinatorics and probability. The essential difference between them is whether the order of the selected items matters.

Key Differences

Understanding when to use a permutation versus a combination is the most important step. This table breaks down the main distinctions.

FeaturePermutationCombination
OrderThe order of the items matters. (e.g., "1, 2, 3" is different from "3, 2, 1")The order of the items does not matter. (e.g., "1, 2, 3" is the same as "3, 2, 1")
ExampleChoosing the first, second, and third place winners in a race.Choosing a team of three people from a group.
FormulanPr = n! / (n - r)!nCr = n! / (r! * (n - r)!)

How to Use This Calculator

  1. Select whether you want to calculate a Permutation (nPr) or a Combination (nCr).
  2. Enter the total number of items in the set (n).
  3. Enter the number of items you want to choose from that set (r).
  4. The calculator will automatically show the total number of possible arrangements or groups.

Note: The calculations involve factorials (n!), which grow extremely quickly. This calculator supports inputs for 'n' up to 170. Any value higher than that will result in a number too large for standard calculations.