iCloud sync limitations

Limits for iCloud Contacts, Calendars, Reminders, and Bookmarks

To help iCloud keep your Contacts, Calendars, Reminders, and Bookmarks up to date, keep your information within these limits.

Calendars and Reminders

  • Total number of calendars, events, and reminders: 50,000*

  • Maximum combined number of calendars and reminder lists you can have: 100*

  • Maximum size of all calendar and reminder data (not including attachments): 1GB*

  • Maximum number of characters in a reminder title: 1,000*

  • Maximum size of a calendar event including attachments: 20MB

  • Maximum number of attachments per event: 20

  • Maximum number of attendees you can invite to an event: 300

  • Maximum number of people with whom you can share a private calendar: 100

* If you have upgraded your iCloud reminders on a device running iOS 13, iPadOS, or macOS Catalina, these limits on reminders do not apply. Learn more about the Reminders upgrade process.

Contacts

  • Total number of contact cards: 50,000

  • Maximum size of a contact card: 256KB

  • Maximum size of a contact photo: 224KB

  • Maximum size of a contact group: 256KB

  • Maximum size of all contact cards:

    • Card text: 48MB

    • Card photos: 200MB

  • Supported file types for a contact photo: JPEG, BMP, PNG, GIF

  • vCard import limits:

    • Total number of vCards: 50,000

    • Maximum size of a vCard: 256KB (photo + text)

    • Maximum photo size for a vCard: 224KB

Bookmarks

  • Total number of bookmarks: 25,000

  • Maximum size of a bookmark: 4KB

  • Maximum size of all bookmarks: 24MB