Math Calculators
Permutation and Combination Calculator
Compute permutations (nPr) and combinations (nCr).
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About the Permutation and Combination Calculator
Permutations count ordered arrangements; combinations count unordered selections. Enter the total number of items (n) and how many you choose (r) and the calculator returns both nPr (permutations) and nCr (combinations). It's a must for probability, statistics, and combinatorics problems.
How to use the Permutation and Combination Calculator
- 01Enter your n (total items) and r (chosen).
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What's the difference between permutation and combination?
Permutations count order (arrangements); combinations don't (selections). There are always more permutations than combinations.
What are the formulas?
nPr = n! ÷ (n−r)! and nCr = n! ÷ (r!(n−r)!). This tool computes both.