Maths & numbers
Combinations & permutations
Count ordered or unordered selections without replacement.
A clear answer. Here’s how.
Combinations nCr = n!/(r!(n−r)!), while permutations nPr = n!/(n−r)!. Items are distinct and selections are without replacement. Uses exact BigInt arithmetic.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Total items (n)
- 10
- Items selected (r)
- 3
Example result
- Combinations (unordered)
- 120
- Permutations (ordered)
- 720