Excel WEEKNUM Function

HomeExcel FunctionsExcel WEEKNUM Function (Example + Sample File)


The Excel WEEKNUM Function is listed under Microsoft Excel's Date Functions category. It returns the week number of the date supplied. In simple words, WEEKNUM returns the week number of date which you specify ranging from 1 to 54.

How to use it

To learn how to use the WEEKNUM function in Excel, you need to understand its syntax and arguments:




  • serial_number: A date for which you want to get the week number.
  • [return_type]: A number to specify the starting day of the first week of the year. You have two systems to specify the starting date of the week.


  • If the supplied date is out of range for the current database value, a #NUM! is returned.
  • If the return type is out of the range specified in the table above, a #NUM! is returned.


To master the WEEKNUM function we need to try it out in an example, so make sure to check out the below one:

In the below example, we have used TODAY with WEEKNUM to get the week number of the current date.

It will update the week number automatically every time the date changes.

In the below example, we have added text “Week-” with the week number for a meaningful result.

Related functions

This tutorial is the part of our Excel Functions with Examples (Function Guide) and below are some of the related functions:

About the Author

Puneet Gogia

Puneet is using Excel since his college days. He helped thousands of people to understand the power of the spreadsheets and learn Microsoft Excel. You can find him online, tweeting about Excel, on a running track, or sometimes hiking up a mountain.