Education & Math Tools

Combinations & Permutations Calculator

Enter n (total items) and r (items chosen) to calculate both permutations (order matters) and combinations (order doesn't matter).

720
Permutations, P(n,r) — order matters
120
Combinations, C(n,r) — order doesn't matter

How to use this tool

  1. 1Enter n and r.
  2. 2See P(n,r) permutations and C(n,r) combinations.

Frequently asked questions

When do I use permutations vs. combinations?+

Use permutations when order matters (like arranging a race's finishers); use combinations when only the group selected matters (like choosing a committee).