CalDAV and CardDAV 101

CalDAV and CardDAV are open, internet-based standards for syncing your calendar and contacts across different devices and services.

What They Do

• CalDAV (Calendar): Allows you to sync your appointments, events, and reminders. If you add an event on your phone, it instantly appears on your laptop.
• CardDAV (Contacts): Allows you to sync your address book. Update a phone number once, and it’s updated everywhere.

Why Use Them in 2026?

• Privacy: Unlike proprietary ecosystems (like iCloud or Google), you can host your own CalDAV/CardDAV server. This means your personal data stays on your own hardware.
• Interoperability: These standards work across all platforms—iOS, Android, Windows, Linux, and macOS all support them natively.
• Decentralization: In an age of “data sovereignty,” many people are moving away from big-tech clouds and back to personal servers (like Nextcloud or Apple Home Server) using these trusted standards.