Let's say you have six bells, each with a different tone, and you want to find the number of unique sequences in which each bell can be rung once. In this example, you are calculating the factorial of six. In general, use a factorial to count the number of ways in which a group of distinct items can be arranged (also called permutations). To calculate the factorial of a number, use the FACT function.
This article describes the formula syntax and usage of the FACT function in Microsoft Excel.
Description
Returns the factorial of a number. The factorial of a number is equal to 1*2*3*...* number.
Syntax
FACT(number)
The FACT function syntax has the following arguments:
- Number Required. The nonnegative number for which you want the factorial. If number is not an integer, it is truncated.
Example
Copy the example data in the following table, and paste it in cell A1 of a new Excel worksheet. For formulas to show results, select them, press F2, and then press Enter. If you need to, you can adjust the column widths to see all the data.
| Formula | Description | Result |
|---|---|---|
| =FACT(5) | Factorial of 5, or 1*2*3*4*5 | 120 |
| =FACT(1.9) | Factorial of the integer of 1.9 | 1 |
| =FACT(0) | Factorial of 0 | 1 |
| =FACT(-1) | Factorial of a negative number returns an error value | #NUM! |
| =FACT(1) | Factorial of 1 | 1 |