Combination and Permutation Calculator

What is a combination and permutation calculator?

A combination and permutation calculator finds nCr and nPr. Example: nCr(5,2) = 10 and nPr(5,2) = 20.

How to use it

Enter n and r, then tap Calculate. r must be between 0 and n.

Formulas

Combinations: nCr = n! ÷ (r! × (n−r)!). Permutations: nPr = n! ÷ (n−r)!. For n=5, r=2: nCr = 120 ÷ (2 × 6) = 10, nPr = 120 ÷ 6 = 20.

Example

For n = 5 and r = 2, nCr = 5! ÷ (2! × 3!) = 120 ÷ (2 × 6) = 10. nPr = 5! ÷ 3! = 120 ÷ 6 = 20. Combinations ignore order, so there are fewer of them than permutations.

Frequently Asked Questions

What is nCr(5,2)?

10.

What is nPr(5,2)?

20.

What is the difference between nCr and nPr?

Combinations ignore order, permutations count order.

More calculators: Math Tools and All Tools.