Summary
For those who don’t want to read the rest, here’s what you do.
- Visit the free service MashiCal & create a calendar
- Add each of your iCal feeds to your MashiCal calendar (adjust settings as appropriate)
- Copy the subscribe link (right-click and ‘copy link’ on the aggregated calendar)
You now have a link to an aggregated iCal feed of your calendar!
Below is the rest of the post for those with more patience ;)
Why would anyone need to do this?
If you have multiple calendars, sharing free/busy information becomes painful. One result is that too much time can be spent scheduling meetings.*
If I could combine all the calendar feeds into one free/busy feed then I’d only have to share that one calendar with colleagues. So far none of the applications I use are able to do this intelligently, and that’s without the additional complexity of having multiple calendars in each application.
Enter MaschiCal.
Using MashiCal to merge .ics feeds
I was already using BusyCal from BusyMac so my Apple iCal calendars sync with Google quite nicely. Therefore, I only need to worry about getting my Google and Outlook calendars into one feed. (NB It’s possible to publish a feed directly from Apple iCal so you don’t need to buy any software)
Getting a feed from Google
To get your ics feed from your google calendar, visit the calendar’s settings page. Make sure the calendar is shared otherwise the feed will not work.
Getting a feed from Outlook
In Outlook 2007 you’ll need to right-click on the calendar you want to create a feed for and “Publish to Internet”. When you’re prompted to share the feed you just created you’ll be able to see the URL you need.
Aggregating the feeds
Now that you have the iCal feeds you want to aggregate, visit MashiCal and put them together. The interface is quite simple and MashiCal will produce an Agenda view and provide a link at the top of the calendar that you can share.
Be aware of the calendar settings for each feed you are entering since timezones and refresh schedules may be relevant. Once it’s done you’ll have a aggregated iCal feed that you can share with others. You can see what my free/busy feed looks like here. I’ve also collated my calendars into a general free/busy page too.
I hope this was useful. I wrote this since it took me a while to discover MashiCal and thought it might be useful for others too.
*I’m aware there are services that try and solve this problem (e.g MeetWithMe and Tungle.Me come to mind). However, I’m more interested in having an aggregated free/busy feed which people can subscribe to.