Instantly list the CalDAV URLs of your iCloud calendars so you can add them to other calendar apps, like Thunderbird. Now updated for macOS Ventura!

Apple's iCloud calendars are based on CalDAV, and they're compatible with Thunderbird and most other calendar programs, if only you can find the secret CalDAV URL of each calendar. This script makes that very easy.

• A Mac desktop or laptop running macOS Ventura (or later?) with your iCloud calendars currently accessible in the Apple Calendar app
  • If you're running Monterey, follow these instructions and let me know if it works.
  • If it doesn't work or you have macOS before Monterey, see "Instructions for older macOS" at the bottom.
• The ability to open Terminal and paste a command
• At least one of:
  • Some familiarity with SQL (and maybe shell scripting) so you can read the short script and see it's safe
  • A friend with same
  • Blind trust in the kindness of a stranger on the Internet

When you run one of the commands in Usage below, you may get some kind of permissions error. In that case, don't reach for sudo—it won't help. Try typing each of these:

ls ~/Library
ls ~/Library/Calendars

...and see if Mac OS gives you some kind of prompt to allow access.

If that doesn't solve it, open 🍎 > System Preferences and go to "Security & Privacy". Then go to "Full Disk Access", click the lock to make changes, click the + button to add an application, and add Terminal. Thanks to @erickvd for this tip.

Paste this in the terminal:

curl -s https://raw.githubusercontent.com/midnightmonster/icloud-calendar-urls/master/icloud_calendar_urls | bash

Or download icloud_calendar_urls and run it with:

bash icloud_calendar_urls

You'll get a nice little report that looks something like this:

iCloud Calendar URLs
====================
You'll need your iCloud email and password when you add these to your calendar app.

* [email protected] (Your Name)
  https://p12-caldav.icloud.com/586234577/calendars/inbox/

* Family (Your Name)
  https://p12-caldav.icloud.com/586234577/calendars/b8e0edb4-1acd-445a-b20e-66a1bf964bb7/

* Work (Your Name)
  https://p12-caldav.icloud.com/586234577/calendars/73C8CF6F-98A5-4D7F-9801-C987F5AC1529/

* A Really Old Calendar (Your Name)
  https://p12-caldav.icloud.com/586234577/calendars/reallyold/

* Calendar Someone Shares With You (Sharer's Name)
  https://p12-caldav.icloud.com/586234577/calendars/b94b384039a761e70d632beb4373eb8d4cac0e06f4133f446b6bcc40b9e159a4/

I'm not sure if the calendars named only with your email address can actually be used or what they contain. They didn't show up pre-Ventura.

Neither script in this repository will work with Monterey. Last I looked, the data may be in a quite similar format to how it was in Big Sur, but icloud_calendar_urls.rb does not look in quite the right place. I do not currently have access to a machine running Monterey to fix it. Patches welcome.

Paste this in the terminal:

curl -s https://raw.githubusercontent.com/midnightmonster/icloud-calendar-urls/master/icloud_calendar_urls.rb | ruby

Or download icloud_calendar_urls.rb and run it with:

ruby icloud_calendar_urls.rb

You'll get a nice little report that looks something like this:

iCloud ([email protected])
================================

* Family 
  https://p12-caldav.icloud.com/586234577/calendars/b8e0edb4-1acd-445a-b20e-66a1bf964bb7/

* Work 
  https://p12-caldav.icloud.com/586234577/calendars/73C8CF6F-98A5-4D7F-9801-C987F5AC1529/

* A Really Old Calendar 
  https://p12-caldav.icloud.com/586234577/calendars/reallyold/

* Calendar Someone Shares With You (Sharer's Name)
  https://p12-caldav.icloud.com/586234577/calendars/b94b384039a761e70d632beb4373eb8d4cac0e06f4133f446b6bcc40b9e159a4/

Macs come with some version of ruby since quite a long time, and this short script uses only standard library modules that have been around for many years, so it should run on your Mac. But I've only actually tried it on my own system, so your mileage may vary.