nCr
Combinations Calculator
How many ways to choose r items from n when the order does not matter, exactly.
Result…
How it's calculated
Without repetition: C(n, r) = n! ÷ (r! × (n − r)!) With repetition: C(n + r − 1, r)
Combinations count selections where order does not matter: a poker hand, a lottery draw, a committee. The count is exact (whole-number arithmetic with no rounding); very large results are shown in scientific notation with the exact digits below when they fit. If order matters, use permutations.
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