# COMBIN

## Content

This function calculates the number of possible combinations for a specified number of items.

## Syntax

`COMBIN(k, n)`

## Arguments

This function has these arguments:

| Argument | Description |
| -------- | ----------- |
| *k* | [Required] Number representing the number of items; if not an integer, the number is truncated; must be positive and greater than or equal to*n* |
| *n* | [Required] Number of items in each possible permutation; if not an integer, the number is truncated; must be positive |

## Remarks

A combination is any set or subset of items, regardless of the internal order of the items. Contrast with permutation (the [PERMUT](/document-solutions/dot-net-excel-api/docs/online/formula-reference/statistical-functions/permut) function).
The number of combinations is calculated as follows:
![](https://cdn.mescius.io/document-site-files/images/8d606653-16a0-474d-b9dc-e2b4d01c2446/images/Func-COMBIN.png)

## Examples

`COMBIN(C4,B2)`
`COMBIN(B3,5)`
`COMBIN(R1C2,2)`
`COMBIN(8,2)` gives the result 28
`COMBIN(100,3)` gives the result 161700