Enter n and r for permutations nPr (order matters) and combinations nCr (order-free).
How to use
- Enter integers with 0 ≤ r ≤ n.
- Compare nPr vs nCr—lineups vs committees.
Example
Pick 3 from 10 in order → 720; same pick without order → 120.
For independent event odds, see the probability calculator.
Notes
Permutations count ABC and BAC as different; combinations do not.
Frequently asked questions
Permutation vs combination?
nPr counts order; nCr does not.
What are n and r?
n = pool size, r = picks, with 0 ≤ r ≤ n.
Why is n limited?
Factorials explode; very large n exceeds precise display limits.
Link to probability?
Count arrangements here; multiply independent odds on the probability calculator.
Can I save my inputs?
Yes. Copy link below the form keeps your current inputs so you can share the scenario or save it for later.