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Permutation and Combination Calculator

Count permutations (nPr, order matters) and combinations (nCr, order doesn't), with and without repetition.

Change the values and press Calculate to work out your own figures.

Enter the number of objects and how many are chosen.

About number of objects (n)How many things there are to choose from.
About number chosen (r)How many are chosen.
Result
Permutations and combinations
nPr = 30, nCr = 15
With repetition: n^r ordered
36
With repetition: C(n + r − 1, r) unordered
21

Choosing 2 of 6: 30 ordered arrangements, 15 unordered selections.

Show the working
  1. nPr = n! ÷ (n − r)! = 6! ÷ 4! = 30
  2. nCr = n! ÷ (r! (n − r)!) = 15

How to use it

Enter the number of objects and how many are chosen.

Probabilities can be typed as decimals, fractions or percentages. Show the working gives the formula with your numbers in it.

Key facts

nPr = n! ÷ (n − r)!;  nCr = n! ÷ (r! (n − r)!)

Order matters or not?

Choosing a president, secretary and treasurer is a permutation (who gets which job matters); choosing a committee of three is a combination.

Questions

What is 6P2 and 6C2?

30 and 15.

How many lottery combinations are there in 6 from 49?

13,983,816.

Formulas

nPr = n! ÷ (n − r)!;  nCr = n! ÷ (r! (n − r)!)

Sources

Limitations

  • Probabilities can be typed as decimals (0.25), fractions (1/4) or percentages (25%).

Formula version 0.1.0Reviewed