Combinations & Permutations
Calculate nCr and nPr in one place.
Combinations (order doesn't matter)
C(52, 5)
2,598,960
Permutations (order matters)
P(52, 5)
311,875,200
Combinations count groups of r picked from n. Permutations count ordered arrangements. C(52, 5) is poker hands. P(10, 3) is 3-digit codes from 10 digits without repeats.
About
How many ways can you pick r items from n? Combinations count groups (order doesn't matter); permutations count arrangements (order matters). C(52, 5) = 2,598,960 poker hands. P(10, 3) = 720 ways to assign 3 distinct prizes among 10 people.
How to use
- Enter n (total items).
- Enter r (chosen).
- Read both nCr and nPr.
FAQ
When do I use combinations vs permutations?+
If reordering the same group counts as different, use permutations (a race finish, a passcode). If reordering doesn't matter, use combinations (a poker hand, a committee).