Date Level: Intermediate Available in: Excel 2013+
In this article Syntax Examples Example 1 Related functions ISOWEEKNUM returns the ISO 8601 week (weeks start on Monday; week 1 holds the first Thursday). Use it when European teams or SAP reports say “week 1”, because WEEKNUM can disagree around New Year.
Syntax
=ISOWEEKNUM(date)
Argument
What it means
dateA date.
Examples
Example 1
=ISOWEEKNUM(DATE(2016,1,1))Returns 53 — 1 Jan 2016 belongs to the last ISO week of 2015.
WEEKNUM · WEEKDAY
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Written by Atul Vij Atul (AJ) builds office-automation and local-first AI tools as Atulya AI, and works with Excel, SAP and Oracle EPM every day. He writes about the shortcuts, macros and automations that actually save time — plus the occasional wacky fact.
More posts by Atul → ← Previous CELL Function in Excel: Information About a CellNext → DAY Function in Excel: Day of the Month✨ Ask AI about this article Stuck on a step? Ask a question and the AI answers using this article.
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