Tutorial: Setting Up Auto-Refresh for Live Calendar Sync
Posted: July 15, 2026 · 2 min read
What auto-refresh does
When auto-refresh is enabled, manyCalendars automatically re-fetches all your URL-based calendars (ICS feeds) and re-syncs all your tab-based calendars every time you open the extension. This means your unified view is always current without any manual action.
Without auto-refresh, manyCalendars displays the calendar data from your last manual sync. That data might be minutes old or hours old, depending on when you last clicked refresh. For busy professionals with calendars that change frequently, stale data means missed conflicts.
How to enable it
1. Open manyCalendars by clicking the extension icon in your browser toolbar.
2. Click the gear icon in the top-right corner to open Settings.
3. Under the "Sync" section, toggle "Auto-refresh on open" to ON.
4. Close settings. The next time you open manyCalendars, all calendars will refresh automatically.
That is it. No intervals to configure, no schedules to set. manyCalendars refreshes once when you open it, using the freshest data available at that moment.
Auto-refresh vs manual refresh
Use auto-refresh when: your calendars change frequently throughout the day, you want a "set it and forget it" experience, or you open manyCalendars multiple times per day and want fresh data each time.
Use manual refresh when: you have many tab-based calendars and the refresh takes a noticeable moment, you want to control exactly when syncing happens (for instance, after you know a meeting was just scheduled), or you are on a metered connection and want to minimize network requests for ICS feeds.
You can always trigger a manual refresh regardless of the auto-refresh setting by clicking the refresh icon in the topbar. Auto-refresh does not prevent manual refreshes. It just ensures you start with current data.
What happens during a refresh
For URL calendars: manyCalendars fetches the ICS file from the URL you provided. It parses the updated events and replaces the previous data for that calendar. If the URL is unreachable (network error, expired link), the previous data is preserved and an error badge appears on that calendar in the sidebar.
For tab calendars: manyCalendars reads the current state of the browser tab associated with that calendar. If the tab is still open, it syncs the visible events. If the tab has been closed, it displays the last known data and shows a "tab closed" indicator.
Refresh time depends on the number of calendars and their source type. URL feeds typically complete in 1-3 seconds. Tab syncs are near-instant since the data is already loaded in the browser.
Always up to date, never a surprise. That is the point of auto-refresh and that is the point of manyCalendars. Install it and stop wondering if the calendar you are looking at is still accurate.