Permutation and Combination Calculator

A distinct combinatorics page that broadens the math/stats wedge beyond inference into counting problems with strong classroom and exam intent. Use the tool above to enter a few clear inputs and get a practical answer you can use right away.

This permutation and combination calculator helps students quickly compute nCr and nPr values without expanding factorial formulas by hand. Enter the total number of items, the number selected, and whether order matters to get the answer instantly.

For combinations, the calculator uses nCr = n! / (r! × (n-r)!). For permutations, it uses nPr = n! / (n-r)!.