This combination calculator finds the number of ways to choose a sample of items from a larger set when order does not matter. Enter the total number of objects (n) and the number of items in your sample (r). For example, the combination calculator can tell you how many ways you can choose 4 books from a shelf of 10 books. If the order items in the sample does matter, use the Permutation Calculator instead.
You can choose whether sampling is without replacement (default) or with replacement. The calculator will show the correct combination notation, the final answer, a plain-language explanation, and a step-by-step solution. Below the combination calculator, you’ll find more information about interpretations and using its output. See all my Statistical Calculators!