Back to Help Centre

Calendar Integrations

Connect your existing calendars and Chronos keeps events lined up automatically in both directions.

By Byte Size Labs · Updated 13 April 2026

Why Connect Your Calendars?

Connecting your external calendars to Chronos Calendar keeps everything lined up automatically. Events from Google Calendar, Outlook, or other sources appear in Chronos on their own, and tasks you create in Chronos flow back the other way too.

Benefits of Calendar Integration:

  • One unified view of all your events and meetings
  • AI scheduling respects your external meetings
  • No double-booking between calendars
  • Changes update automatically in both directions
  • Keep using your preferred calendar app whilst benefiting from AI scheduling

Supported Calendar Providers

Chronos Calendar integrates with the following calendar services:

Google Calendar

Stays in step both ways, with real-time updates
  • OAuth 2.0 secure authentication
  • Access to all your Google calendars
  • Real-time webhook notifications, so changes land instantly
  • Events update on both sides automatically

Microsoft Outlook / Office 365

Updates both ways, in real time
  • Microsoft Identity Platform authentication
  • Works with Outlook.com and Office 365 accounts
  • Real-time webhook notifications via Microsoft Graph API
  • Events update on both sides automatically

iCal Feeds (.ics)

Read-only, one-way updates
  • Subscribe to any public iCal feed URL
  • Periodic polling for updates (every 15–30 minutes)
  • Only flows one way — read-only from the external source
  • Works with Apple Calendar and services that export .ics feeds

Connecting Google Calendar

Step-by-Step Setup

  1. Navigate to Integrations

    Go to Settings > Integrations or Settings > Connected Calendars

  2. Click "Connect Google Calendar"
  3. Authorise Chronos Calendar

    You'll be redirected to Google's login page. Sign in with your Google account if you're not already logged in.

  4. Grant permissions

    Google will ask to view and edit events on your calendars. Click "Allow" to proceed.

  5. Select calendars to connect

    Choose which Google calendars to bring into Chronos.

  6. Done!

    Your Google Calendar events now appear in Chronos, and changes carry over automatically from then on.

Success! Your Google Calendar is now connected. Events update automatically in both directions.

Connecting Microsoft Outlook

Step-by-Step Setup

  1. Navigate to Integrations

    Go to Settings > Integrations or Settings > Connected Calendars

  2. Click "Connect Microsoft Outlook"
  3. Sign in with Microsoft

    Sign in with your Microsoft account (Outlook.com, Office 365, or work account).

  4. Grant permissions

    Allow Chronos to read and manage your calendar events. Click "Accept" to proceed.

  5. Select calendars to connect

    Choose which Outlook calendars to bring in. Your events import into Chronos automatically.

Subscribing to an external calendar

Import events from TutorBird, Apple Calendar, Calendly, or any public iCal URL. Imported events appear on your calendar as read-only and refresh automatically every 15 minutes so the AI scheduler can plan your work around them.

  1. Get your iCal feed URL from your calendar service (usually ends in .ics or starts with webcal://)
  2. Go to Settings > Integrations > "Subscribe to a calendar" and paste the URL
  3. Click Validate to preview the feed, then pick a name and colour and click Subscribe
  4. Chronos imports the events immediately and checks for updates every 15 minutes
Note:Subscribed calendars are read-only. Events imported from an external feed cannot be edited, moved, or deleted in Chronos, and any changes you make in Chronos won't flow back to the source. You can subscribe to up to 10 external calendars per account.

How Two-Way Sync Works

Two-way synchronisation means changes flow in both directions between Chronos and your external calendar.

From External Calendar → Chronos

  • Events arrive as fixed-time items: Meetings and appointments from your external calendar appear in Chronos as "Events" (not flexible tasks)
  • Details carry over: Event title, description, start/end times, and location all come across
  • Changes flow through automatically: If you change an event in Google/Outlook, it updates in Chronos within moments
  • Deletions carry over too: Deleted events in external calendars are removed from Chronos

From Chronos → External Calendar

  • Scheduled tasks appear too: Tasks with scheduled start and end times appear in your external calendar
  • New events carry over: Events you create in Chronos appear in your connected calendar
  • Edits flow back: Changes to title, time, or description update on the other side too
  • Colours preserved: Task colours/categories in Chronos map to calendar colours
Real-Time Updates: For Google Calendar and Microsoft Outlook, Chronos uses webhooks to receive instant notifications when events change. Updates appear in seconds, not minutes.

Managing Your Calendar Connections

Viewing Connected Calendars

Go to Settings > Integrations to see all your connected calendars. You'll see:

  • Calendar provider (Google, Microsoft, iCal)
  • Calendar name
  • Last sync time
  • Sync status (active, error, disabled)

Manual Sync

Updates happen automatically, but you can trigger one by hand if needed:

  1. Go to Settings > Integrations
  2. Find the calendar you want to update
  3. Click "Sync Now" or the refresh icon
  4. Wait for it to finish

Disconnecting a Calendar

To disconnect a calendar:

  1. Go to Settings > Integrations
  2. Find the calendar you want to disconnect
  3. Click "Disconnect" or the delete icon
  4. Confirm the disconnection

Note: Disconnecting a calendar removes its events from Chronos, but leaves your external calendar untouched.

Troubleshooting Sync Issues

Events Not Syncing?

  • Check that the calendar connection is still active in Settings > Integrations
  • Try updating it by hand with the "Sync Now" button
  • Verify you haven't revoked permissions in Google/Microsoft settings
  • Check the connection's status for error messages

Duplicate Events Appearing?

This can happen if you've connected the same calendar twice. Check Settings > Integrations and remove duplicate connections.

Authentication Errors?

If you see "Authentication failed" or similar errors:

  1. Disconnect the calendar
  2. Reconnect it with fresh authentication
  3. Make sure you grant all requested permissions

Slow Sync for iCal Feeds?

iCal feeds update every 15–30 minutes, not instantly. This is normal behaviour. For instant updates, use Google Calendar or Microsoft Outlook instead.

Best Practices

  • Connect your primary calendar first

    Start with your main work or personal calendar before adding others

  • Be selective with iCal feeds

    Only subscribe to feeds you regularly reference — too many can clutter your calendar

  • Keep an eye on your connections

    Periodically check Settings > Integrations to make sure every calendar is still connected and up to date

  • Don't create duplicate events

    If a meeting is already in your Google Calendar, don't recreate it in Chronos — it will appear on its own

  • Use Chronos for task management

    Create flexible tasks in Chronos and let AI schedule them around the meetings pulled in from your connected calendars

Other integrations

Looking for non-calendar integrations?

Need more help? Contact support or return to help centre