The Excel COMBIN function returns the number of combinations — how many ways you can choose a group of items from a larger set when order does not matter and items are not repeated.
Syntax
| Argument | Description | |
|---|---|---|
number | Required | The total number of items to choose from (n). |
number_chosen | Required | How many items are chosen in each group (k). Must be between 0 and number. |
How to use it
COMBIN answers “how many different groups of k can I pick from n items?” when order is irrelevant and nothing repeats. It is the classic n choose k.
Under the hood, COMBIN(n,k) = FACT(n) / (FACT(k) * FACT(n-k)). Use it for lottery odds, poker hands, or any “choose a committee” count. When order does matter, use PERMUT instead; when repetition is allowed, use COMBINA.
Order vs no order: COMBIN ignores order, so {A,B} and {B,A} count once. If picking 1st/2nd/3rd place where order matters, use PERMUT, which gives larger counts.
Try it: interactive demo
Pick a COMBIN example to see the formula and its result.
Practice workbook
Frequently asked questions
What does COMBIN calculate?
number_chosen items from number total when order doesn't matter and items aren't repeated. =COMBIN(5,2) = 10.How many 5-card poker hands are there?
=COMBIN(52,5) = 2,598,960 — the number of distinct 5-card hands from a 52-card deck.What is the difference between COMBIN and PERMUT?
When should I use COMBINA instead?
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