Sync a calendar from a browser tab (Pro)
Last updated: June 10, 2026 · 3 min read
When you need Tab Sync
Some corporate calendars cannot be exported. IT disables ICS publishing, blocks API access, and locks down third-party integrations. You can see the calendar in your browser, but nothing can pull it out.
Tab Sync is built for exactly this case. If you can open the calendar in a browser tab, manyCalendars can read it. No export, no admin rights, no IT ticket.
Tab Sync is a Pro feature. If you are on the free plan, you can upgrade to Pro to unlock it.
Before you start
- A Pro plan. Tab Sync is part of Pro, alongside unlimited calendars and auto-busy blocking.
- A valid login session. You must be signed in to the calendar in your browser. manyCalendars reads the page the same way you do, so it needs your live session.
That is the whole list. The capture runs entirely on your device. Nothing is uploaded anywhere, and no credentials are stored or entered on your behalf.
Step by step
- Open the corporate calendar in a browser tab. Sign in if prompted. If you can see your events, you are ready.
- Open manyCalendars and click Add Calendar.
- Choose the Tab method.
- Pick the tab that shows your calendar from the list.
- Give the calendar a name and confirm.
Within a few seconds, the events appear in your unified view, color coded like every other calendar.
Tip: Name the calendar after the client, not the platform. Once you have three Outlook calendars in the sidebar, "Client A" is a lot more useful than "Outlook".
What happens behind the scenes
manyCalendars reads the visible month plus the next month. That gives you a rolling two-month window of events, which covers the planning horizon most schedules actually use.
Refreshes happen silently in the background. manyCalendars opens its own work tab, reads the calendar, and closes that tab when it is done. You do not need to keep the original tab open, and you will not see the refresh happen.
Everything stays local. The sync uses your browser and your session, and the events are stored on your device. There is no cloud sync and no server in the middle.
If events stop updating
Tab Sync depends on your login session. Many corporate tenants sign you out after a set period, and once that happens the background refresh cannot read the page.
The fix is simple: open the calendar in a tab, sign in again, and the next capture picks up where it left off. No settings to change, nothing to re-add.
Still stuck? Browse the rest of the Help Center or email support@manycalendars.com. And if you have not unlocked Tab Sync yet, it is included in every Pro plan.