Which calendars does Cronofy sync?

When a user connects a calendar account, Cronofy syncs the calendars that belong to that account. Exactly which calendars that includes depends on the calendar provider.

Calendar providers

Google #

We sync the calendars listed under My calendars in Google Calendar. We don’t sync calendars listed under Other calendars.

Syncing a calendar shared by someone else #

A calendar shared with the user by someone else only appears under My calendars, and so is only synced, if its owner shared it with the Make changes and manage sharing permission. Google’s Share your calendar guide explains how to share a calendar with this permission, and how the user then adds it to their account.

If Make changes and manage sharing isn’t available, the organization’s Google Workspace admin may have restricted calendar sharing.

If the permission is lowered later, we stop syncing the calendar and List Calendars shows it with calendar_deleted set to true.

Microsoft 365 and Outlook.com #

We sync calendars owned by the connected account. While calendars shared with the user from another mailbox may still connect, we don’t directly test or support this, and can’t guarantee a working sync.

With Enterprise Connect, shared mailboxes can be connected separately. See Shared calendars.

Apple iCloud #

We sync every iCloud calendar the user created. We don’t sync Reminders lists, or anything else that only holds tasks.

Calendars that show in the Calendar app on a Mac or iPhone but aren’t stored in iCloud can’t be synced. This includes calendars listed under On My Mac and calendars from other accounts, such as Google. To check whether a calendar is stored in iCloud, sign in at icloud.com with the Apple ID that was connected and look for it in Calendar.

New iCloud calendars are picked up automatically, so the user doesn’t need to reconnect their account. Reconnecting picks them up straight away.

FAQs

What happens to calendars the user can’t edit? #

If the user can’t edit a calendar we sync, it’s synced as read-only. Its events are still included, but events can’t be created, updated or deleted in it. List Calendars shows these calendars with calendar_readonly set to true.

Does your application check every synced calendar? #

Syncing a calendar doesn’t mean your application checks it. To see which calendars we’re syncing for a user, call List Calendars.

Your application decides which of those calendars count toward availability, for example with calendar_ids in an Availability Query or with Availability Rules. See Why am I seeing free slots during booked events? for more information.