How to Get the Week Number with WEEKNUM in Excel

Find the week of the year for orders with WEEKNUM, switch to Monday-start weeks, and work out the week of the month.

You will learn to

• Return the week number of a date
• Switch the week start with return type 2
• Calculate the week of the month

How it works

WEEKNUM(date) returns the week of the year. By default (return type 1) weeks start on Sunday and week 1 is the week that contains January 1, so it can be only a few days long. Return type 2 starts weeks on Monday.

To get the week of the month, subtract the week number of the 1st of that month and add 1: =WEEKNUM(B2)-WEEKNUM(DATE(YEAR(B2),MONTH(B2),1))+1. For international ISO weeks use ISOWEEKNUM instead.

=WEEKNUM(B2)