Week numbers in iPhone & iPad
To enable or display the ISO 8601 week number in iPhone & iPad, you typically need to adjust the view settings:
Settings > Calendar > Turn on "Week Numbers"
* Ensure your system or application regional settings are set to follow ISO 8601 standards (weeks start on Monday) if the output varies.
Instructions étape par étape
- Open the Settings app on your iPhone or iPad.
- Scroll down and tap Calendar (on iOS 18+ it is under Apps > Calendar).
- Toggle on "Week Numbers".
- Open the Calendar app and switch to the month view: the ISO week number appears at the left edge of each row.
Bon à savoir
Apple's Calendar always uses ISO 8601 numbering (weeks start Monday), so the number matches the standard used across Europe. The setting only affects month view, not day or list views.