About the Permutation and Combination Calculator
Find nPr and nCr for any n and r. This tool is free, works in your browser and needs no sign-up.
How to use the Permutation and Combination Calculator
Enter the total number of items n and the number you choose r.
Formula used
nPr = n! ÷ (n − r)!. nCr = n! ÷ (r! × (n − r)!).
Example
With n (total items) 10, r (items chosen) 3, the calculator shows: Permutations (nPr) = 720; Combinations (nCr) = 120.
Frequently asked questions
Is the Permutation and Combination Calculator free to use?
Yes. It is completely free and you can use it as many times as you like.
How accurate is the Permutation and Combination Calculator?
The calculator uses standard formulas, so the maths is exact. Real life results can differ because of fees, taxes, rounding or personal factors, so treat the answer as an estimate.
Do you store the numbers I enter?
No. All calculations run in your browser. The values you type are not sent to our server.
Disclaimer: results are estimates for information only. They are not financial, medical or professional advice.