Combination Calculator
Calculate the number of unordered selections (combinations) of r items from n.
About this calculator
The Combination Calculator on NumberCals is a free, mobile-friendly tool for anyone needing to calculate the number of unordered selections (combinations) of r items from n. Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.
Formula used
nCr = n! / (r! · (n − r)!)
What you'll need
- n (total items) (e.g. 10)
- r (items chosen) (e.g. 3)
What you'll get
- Combinations (nCr)
Formula
nCr = n! / (r! · (n − r)!)
Result
Frequently Asked Questions
When do I use combinations? +
When order doesn't matter — e.g. picking 5 cards from a deck (poker hands) or choosing committee members.
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