About this tool
Count the ways to arrange or choose r items from n, with and without repetition.
nPr = n! ÷ (n − r)!, nCr = n! ÷ (r!(n − r)!). With repetition: arrangements nʳ, selections C(n + r − 1, r).
Formula: nPr = n!/(n−r)! · nCr = n!/(r!(n−r)!)
Example: Total items (n) = 10, Items chosen (r) = 3 → Permutations (nPr) = 72, Combinations (nCr) = 12.
Very large results are shown in scientific notation.
Quick steps
- Enter your values — every field shows its unit.
- Press Calculate (or Try an example to see how it works).
- Read the results and copy them if you need them elsewhere.
The calculation runs in your browser. Nothing you type is sent to 1CLIK.
FAQ
How does the Permutation and Combination Calculator work?
nPr = n! ÷ (n − r)!, nCr = n! ÷ (r!(n − r)!). With repetition: arrangements nʳ, selections C(n + r − 1, r).
What should I keep in mind?
Very large results are shown in scientific notation.
Is my data sent anywhere?
No. The numbers stay on your device; the page only shows the result.