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Weeknum function in Excel
Hello, By using WEEKNUM("08/03/2021") function in Excel or Google sheet, the result is 32. However, by using https://www.whatisthedatetoday.com/week-numbers-2021.html and other websites, they show t...
Rosy_888 By default, WEEKNUM starts counting weeks from the first of January and weeks start on Sunday's. In 2021, January 1st, was on a Friday. Hence, week 1 for 2021 only contains 2 days (Friday, Saturday) with week 2 starting Sunday the 3rd. Another week numbering standard was issued by the ISO and counts full weeks, starting on Mondays. Hence, the first full week of 2021 (=week 1) started Monday, January 4. In Excel, this standard is used by the ISOWEEKNUM function.
With WEEKNUM, you change the outcome by setting one of 10 optional arguments (1 or 2 to choose Sunday or Monday as the first day of the week, 11-17 to choose starting days from Monday to Sunday and 21 to use the ISO standard).