📅 Calendar Open source Privacy ★★★★★
Nextcloud Calendar
Self-hosted CalDAV calendar
Overview
Nextcloud Calendar is standards-based groupware you host—full control over schedule data.
Works with iOS/macOS Calendar, Thunderbird, DAVx5, etc.; pairs with Deck, Tasks, and Talk.
Managed Nextcloud hosts (Hetzner, etc.) reduce ops for non-experts.
Scores
Privacy 5/5
Ease of use 3/5
Features 5/5
Value 5/5
Google Calendar — comparison
Data on your server, CalDAV avoids lock-in—Meet replaced by Nextcloud Talk; no Google AI on events.
Pros
- ✓ CalDAV/CardDAV—any compatible client
- ✓ Integrated with files, contacts, tasks, video
- ✓ Full data sovereignty
- ✓ Shared calendars and delegation
Cons & caveats
- − Self-hosting skills required (unless managed)
- − No default E2EE for calendar data
- − Setup takes time
Best for
- Self-hosting advocates
- CalDAV standard priority
- Whole Google Workspace replacement
Not ideal for
- Zero server administration
- Mandatory E2EE calendar
Specs
- Pricing
- Self-hosted — Software free. VPS ~€5/month+ or managed hosting ~€4/month+.
- Difficulty
- Advanced
- Data location
- Your self-hosted server location.
- Platforms
- Self-hosted · CalDAV clients · Web
CalDAV/CardDAV標準Deck/Tasks連携完全データ主権
Migration from Google Calendar
- 1 Deploy Nextcloud instance
- 2 Export Google Calendar .ics and import
- 3 Configure CalDAV URLs on each client
- 4 Rebuild shared calendar permissions
Setup steps
- 1 Install Nextcloud on VPS or NAS
- 2 Enable Calendar app
- 3 Import Google .ics file
- 4 Add CalDAV account on iOS/macOS/Thunderbird