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ISOWEEKNUM Function – Google Sheets

November 9, 2025January 13, 2018 Adam Steinfurth

The ISOWEEKNUM function accepts a date and returns the ISO week number (1 through 54) of that date. The date must be in a valid format, so you must use the DATE function, wrap it in quotes, or use a cell reference to a cell containing a date. An ISO week starts on Monday. The … Read more

Categories Date, Date parts Tags date, function, iso, isoweeknum, weeks

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