Week numbers from Google

Google has finally gotten their act together and have added a pretty easy way to add official week numbers, if you know where to look. You have to go to a place called "Interesting Calendars." To get there, press the dropdown button () in the box called "Other calendars", then press "Browse Interesting Calendars," then go to the tab called "More" and subscribe to the calendar called "Week Numbers." In my test it appears that it adds the same calendar regardless of what language you use, and the week numbers are always displayed on Mondays. Google's week numbers look like this: .

If you still want to use my custom calendar, continue reading...

Add the week numbers

To add my week numbers, simply use this box:

Here is an image showing how it will look when you have added the calendar.

Pretty neat, right? I hope these week numbers will make your life easier. I have hosted this calendar since 2006 and it currently contains week numbers throughout 2020.

You can remove the week numbers just as you would any other calendar. Simply go to your settings and press "Unsubscribe". If you just want to turn them off for a while, you can simply press the calendar called "Week Numbers" in your calendar list and the week numbers will disappear until you press it again.

Ensuring correctness

Due to the fact that some countries number weeks a little differently, I encourage you to verify that my week numbers are correct in your country. Pick up a local calendar and make sure the week numbers match. Note that traditional paper calendars often make mistakes with week 53, where they usually label it as week 1. But if you look at the calendar for the next year, the error should be fixed.

Mobile support

Your mileage may vary.

Customizing the week numbers

Use this third party website to generate custom week numbers for your own use: http://optics.eee.nottingham.ac.uk/matt/weeknumbers/weeknumbers_form.php


  • 2016-01-30
    I forgot to add more week numbers, someone had to remind me. Because I don't remember exactly how week numbers that start on Sundays work, I am not updating that calendar. If you used that calendar, switch to Google's week numbers.

    I am adding new week numbers through 2020 for the other calendar. If you still need week numbers after that, you should consider switching to Google's week number calendar.
    Posted Jan 30, 2016, 2:36 PM by Stefan Sundin
  • 2012-09-10
    I am aware of the issue where several duplicate events have been added to the calendar. There seems to be an issue where other people can invite my week number calendar to events, and these will appear to everyone subscribed to the calendar. I have reported the issue to google (here). If you want this issue to be resolved once and for all, please add a comment in the thread to let Google know this is a serious problem. For a quick fix, you can unsubscribe to this calendar and instead start using Google's official week numbers (instruction above). Please be patient and I am confident this issue will be resolved. Thank you.
    Posted Sep 10, 2012, 3:02 AM by Stefan Sundin
  • 2011-09-03
    Sometimes I wish I had a direct line to the GCal team.
    Posted Sep 3, 2011, 12:49 PM by Stefan Sundin
  • 2010-10-06
    Okay. I have received some feedback on the experiment I have been running (see post below this one).

    From what I could determine, there are two negative side effects from changing the length of the week number events. 1) All days are marked as busy (all days are bold in the mini-calendar). Previously only the first day in the week was marked as busy. 2) The week numbers appear on every day in the Agenda view.
    Despite of this, I have decided that the benefits outweigh the side effects, and I will apply this change to all week numbers in the coming days.

    For those of you who despise this change, there is a remedy! You can simply switch to Google's own week number calendar (instructions above). Their calendar is exactly the same as my calendar was before, with the exception of a different icon.

    My final thoughts on this is that I don't think Google has successfully added week numbers to Google Calendar. I think week numbers need to be integrated in the same manner as normal date numbers. Any "solution" that requires an extra calendar will be flawed in some way. My hopes that Google will make week numbers a first class citizen is unfortunately very low.
    Posted Jun 12, 2011, 11:29 AM by Stefan Sundin
Showing posts 1 - 4 of 12. View more »


Adding the week numbers manually

If the button on the top of the page didn't work, then you can try this link:

Google Apps users can make a direct link to add the week numbers to their domain. Simply edit these links to your domain name:

  • https://calendar.google.com/calendar/hosted/example.com/render?cid=g0k1sv1gsdief8q28kvek83ps4@group.calendar.google.com

Just remember to replace example.com with your domain!

Source code

Get the source code here: https://gist.github.com/stefansundin/8413812