Returns the factorial of a number. The factorial of a number is equal to 1*2*3*...* number.
Syntax
FACT(number)
Number is the nonnegative number for which you want the factorial. If number is not an integer, it is truncated.
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example
 Create a blank workbook or worksheet.
 Select the example in the Help topic.
Note Do not select the row or column headers.
Selecting an example from Help
 Press CTRL+C.
 In the worksheet, select cell A1, and press CTRL+V.
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A 
B 
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) 
Negative numbers cause an error value (#NUM!) 
=FACT(1) 
Factorial of 1 (1) 
