Merge Google Calendar and Exchange into one calendar

Google Calendar and Exchange don't merge on their own: each keeps its own events. To have them in one calendar on every device, copy the events from one into the other. On a Mac, Syncom does this with a one-way or two-way sync, and can merge several calendars into one.

The built-in options

Show both side by side

Apple Calendar, Outlook and other apps can show a Google account and an Exchange account together. That's often enough at your desk, but only in apps where both accounts are set up. Your Google calendar still won't show that you're in a work meeting, and coworkers checking your Exchange availability won't see your Google events.

Subscribe to a link

Google Calendar can give you a private address in iCal format for a calendar, under Integrate calendar in its settings, and Outlook on the web can publish one too. Each side can then subscribe to the other's link. The limits:

• Subscriptions are read-only.
• They refresh on the provider's schedule, not as soon as something changes.
• Your Google Workspace or Exchange administrator may turn the option off.
• A subscribed calendar doesn't count toward your free/busy time, so it won't stop people booking over it.

One-way or two-way?

A one-way sync copies events from one calendar into the other. The copies follow the originals: when a meeting moves, its copy moves, and when it's cancelled, its copy goes. A one-way sync never edits or deletes an original.

A two-way sync copies each calendar's events into the other. Edits you make to a full-detail copy go back to the original, and the most recent edit wins. Two-way syncs stay cautious: they only change originals you own and can edit, never a meeting someone else organized, and never delete more than 3 originals in one run.

Each direction has its own rules. A two-way sync can bring Exchange meetings into Google with full details while Google events arrive in Exchange as busy blocks.

Choose one-way when one calendar is the source, like a work calendar you only read. Choose two-way when you want to add and edit events from either side.

Merging several calendars into one

Add a sync for each calendar you want to bring in, all pointing at the same destination. You can add as many syncs as you like. A copy is never copied again, even when several syncs share calendars, so merging doesn't set off loops. Syncom also warns you about duplicate or opposing syncs.

Which calendar should hold the copies?

Copy into the calendar you look at most, or the one other people check. If coworkers book you through Exchange, send your Google events there, as busy blocks if you'd rather they didn't see the details. If your family reads your Google calendar, send work meetings there. If both matter, a two-way sync covers both, with its own rules for each direction.

Set it up with Syncom

1. 1
   Add both accounts to your Mac. In System Settings › Internet Accounts, add your Google account and your Exchange account, with Calendars turned on for each.
2. 2
   Add a sync. From Syncom in the menu bar, add a sync. Pick the Google calendar on one side and the Exchange calendar on the other, then choose the direction: either way, or both.
3. 3
   Choose what copies show. Start each direction from a preset (Full mirror, Title & time only or Busy blocks only) and adjust from there.

Syncom syncs when a calendar changes, when your Mac wakes and when your VPN connects, with a safety-net sync every 5 minutes to 2 hours. A Google event you add on your phone reaches Exchange once your Mac sees the change. Recurring events copy correctly, including one-off changes to a single meeting in a series.