Permutations and Combinations Calculator
Count arrangements and selections of r items from n.
How it works
nPr = n! ÷ (n − r)! and nCr = n! ÷ (r! × (n − r)!). Choosing 3 people from 10 for a ranked podium gives 720 permutations, but choosing 3 for a committee gives 120 combinations because order is ignored.
FAQ
Is this calculator free?
Yes. No signup is needed and nothing you enter is stored.
Is the result exact?
Results are rounded for display. For financial, medical, or legal decisions, confirm with a professional.
Do my numbers leave my device?
No. The calculation runs in your browser.