Week numbers in Google Sheets
To calculate the ISO 8601 week number in Google Sheets, use the following formula:
=ISOWEEKNUM(A1)
* Ensure your system or application regional settings are set to follow ISO 8601 standards (weeks start on Monday) if the output varies.
Step-by-Step Instructions
- Enter your date in a cell, for example A1.
- In another cell type =ISOWEEKNUM(A1) and press Enter.
- For the current week number use =ISOWEEKNUM(TODAY()).
Good to Know
Like Excel, Google Sheets also offers WEEKNUM which defaults to the US system. Use ISOWEEKNUM whenever you exchange week numbers with European partners or business calendars.