Backup calendars
Your calendars back up automatically to iCloud. You can also save or share a copy, and import one back.
1. Automatic iCloud backup
Your calendars save to your iCloud account automatically. If you reinstall the app or get a new device, just sign in to the same iCloud account to get them back. (You can see this in the gear menu, under iCloud Backup.)
2. Save or Share a copy
Open a calendar, tap the Share icon, then choose Share calendar. From there you can Save to Files, AirDrop it, or email it.
3. Import a calendar
Open the gear menu and tap Import Calendars, then pick a saved calendar file from Files or iCloud Drive.