RadicaleA simple CalDAV (calendar) and CardDAV (contact) server.

Radicale

Radicale is a lightweight CalDAV and CardDAV server that enables you to self-host calendars, to-do lists, and contact management without complex configuration. It works out-of-the-box while remaining powerful enough for production environments, supporting standards-based calendar and contact synchronization across multiple clients.

Key Features

• CalDAV & CardDAV Support: Share calendars, to-do lists, journal entries, and business cards through industry-standard protocols.
• Zero Configuration: Works immediately upon installation with sensible defaults, eliminating complicated setup processes.
• File System Storage: All data is stored in simple folder structures on the file system, making backups and management straightforward.
• Security: Built-in authentication to limit access and TLS support for secure connections.
• Extensibility: Can be extended with plugins to add custom functionality as needed.
• Multi-Client Compatible: Works seamlessly with numerous CalDAV and CardDAV clients across different platforms.

Use Cases

• Personal Calendar Hosting: Self-host your calendars and contacts without relying on cloud providers.
• Team Collaboration: Share calendars and contact lists within organizations while maintaining full control over data.
• Privacy-First Setup: Run a calendar and contact server on your own infrastructure for complete data sovereignty.
• Legacy System Integration: Provide CalDAV/CardDAV access to existing calendar and contact management workflows.

Who Is It For

Radicale is ideal for individuals and organizations seeking to self-host calendar and contact services with minimal overhead. It appeals to privacy-conscious users, system administrators managing internal infrastructure, and teams needing a lightweight alternative to commercial calendar servers.