The Excel LEN function returns the length of a supplied text string.
The syntax of the function is:
Where the text argument is the text string that you want to find the length of. This can be supplied to the Len function in any of the following ways:
In the spreadsheet below, the Len function is used to return the length of three different text strings (one of which is empty).
Formulas:
 Results:

Further information and examples of the Excel Len function are provided on the Microsoft Office website.
The Microsoft Office website also provides a description of the Excel LenB function, which is supported by languages that use the doublebyte character set (e.g. Chinese, Japanese, Korean).