How to sync Google Calendar with other calendars

Why sync Google Calendar?

If you keep a personal Google Calendar and use Outlook at work, each calendar only knows about its own events. People who book you in one can't see that you're busy in the other, and that's how double bookings happen.

Method 1: Using Caltsu

Caltsu syncs Google Calendar with Microsoft 365 and Outlook.com calendars, and with other Google accounts.

1. Start a free trial. It runs 14 days and needs no card.
2. Click "Connect account" and sign in with Google.
3. Connect your Microsoft 365 or Outlook.com accounts, or another Google account. Apple iCloud is not supported yet.
4. Put the calendars in one sync group. Sync is two-way.

From then on, every event in one calendar shows up as a Busy block in the others.

What you get with Caltsu

• The other calendars get "Busy" blocks, never the original title, attendees or notes.
• Changes arrive through Google push notifications and Microsoft Graph webhooks, usually within seconds.
• New, moved and cancelled events are picked up without you doing anything.

Method 2: Manual export and import

You can export your Google Calendar and import it into another app:

1. Open Google Calendar settings.
2. Click "Import & export".
3. Export the calendar. Google downloads it as an ICS file.
4. Import the ICS file into your other calendar app.

The import is a one-time copy. Anything that changes afterwards has to be exported and imported again.

Method 3: Subscribe in another app

Some calendar apps can show your Google Calendar directly.

Outlook

1. In Google Calendar settings, open the calendar and copy the "Secret address in iCal format".
2. In Outlook, select "Add calendar", then "Subscribe from web".
3. Paste the address and save.

The subscription is read-only, and Outlook decides how often to refresh it. How to sync Google Calendar with Outlook has the full steps.

Apple Calendar

1. On a Mac, open System Settings > Internet Accounts. On older macOS versions this is in System Preferences.
2. Add your Google account.
3. Turn on Calendars.

This shows your Google events in Apple Calendar. It doesn't copy them into iCloud.

Troubleshooting common issues

Events not syncing?

• Check that you've granted the calendar permissions
• Check your internet connection
• Disconnect the calendar and connect it again

Duplicate events?

• Make sure you're not syncing the same calendar twice
• Check whether two tools are copying the same events

For more fixes, see how to fix Google Calendar sync errors.