Tutorial: Migrating From a Cloud Calendar Aggregator to manyCalendars
Posted: October 28, 2026 · 3 min read
Before you start
If you are currently using Reclaim, Morgen, Clockwise, or any other cloud-based calendar aggregator, switching to manyCalendars takes about 10 minutes. The key difference: manyCalendars runs entirely in your browser. No OAuth connections to your client accounts, no data stored on third-party servers, no IT admin notifications.
You do not need to cancel your old tool immediately. Run both in parallel for a day or two until you are comfortable with the transition.
Step 1: Revoke OAuth tokens from your old tool
Cloud aggregators work by connecting to your Google and Microsoft accounts via OAuth. Those connections persist until you explicitly remove them.
For Google accounts: Go to myaccount.google.com, navigate to Security, then "Third-party apps with account access." Find your old aggregator and click "Remove Access."
For Microsoft accounts: Go to account.microsoft.com, navigate to Privacy, then "Apps and services." Find the aggregator and revoke its permissions.
Do this for every calendar account you connected to the old tool. Until you revoke access, the old service can still read your calendar data.
Step 2: Set up the same calendars in manyCalendars
Install manyCalendars from your browser's extension store. Open it and add each calendar you previously had in your aggregator:
Tab-based calendars: Open Google Calendar or Outlook in a browser tab. manyCalendars detects open calendar tabs and can read events directly from the page. No API connection needed.
ICS feed calendars: If any of your calendars publish an ICS feed URL (check your calendar's sharing settings), paste the URL into manyCalendars's feed subscription panel. manyCalendars fetches and parses the feed locally.
Once all calendars are added, verify that you see the same events you saw in your old tool. Conflict detection activates automatically.
What you gain
Privacy. Your calendars are read and merged on your device, not in our cloud. No third-party server stores your meetings, attendees, or schedule patterns.
No IT dependency. Cloud aggregators show up in your client's admin console as a connected third-party app. manyCalendars does not. No awkward conversations with IT about why a scheduling tool has access to their tenant.
No single point of failure. If Reclaim or Morgen has an outage, your unified calendar disappears. manyCalendars works as long as your browser works.
No subscription lock-in. Most cloud aggregators charge monthly after a trial. manyCalendars is free.
What changes
No AI scheduling. Tools like Reclaim automatically find optimal times and create events for you. manyCalendars does not do this. You make scheduling decisions yourself, with full visibility into your availability.
No automatic sync. Cloud aggregators push changes in real-time via API. manyCalendars reads what is currently displayed in your browser tabs. If a calendar tab is closed, manyCalendars cannot see updates to it until you reopen it.
No smart habits or analytics. Some aggregators track your meeting patterns and suggest optimizations. manyCalendars gives you the unified view and conflict detection. You bring the judgment.
For most contractors and consultants, this trade-off is worth it. You get privacy, independence, and simplicity. You give up automation features that most people never fully trusted anyway.
Ready to make the switch? Install manyCalendars and you will be set up faster than it took to read this tutorial.