Radicale is a CalDAV and CardDAV server that provides calendar, to-do list, and contact sharing through open standards.
Radicale solves the problem of self-hosting calendar and contact data without relying on centralized services. It implements the CalDAV and CardDAV protocols, allowing standard clients to synchronize events, tasks, journal entries, and business cards. The server stores all data directly on the file system in a simple folder structure, making it transparent and portable. It requires minimal setup to run and can be secured with TLS and authentication controls.
Radicale suits developers and organizations wanting lightweight calendar and contact infrastructure they control completely. It works out-of-the-box without complex configuration, making it accessible to users without deep server administration experience. The tool integrates with many existing CalDAV and CardDAV clients across different platforms. For those needing customization, the project supports plugins to extend functionality. Anyone evaluating adoption should know that data lives in straightforward file-system folders, which simplifies backup and migration but differs from database-backed alternatives.
The project maintains steady engagement with users through its wiki, issue tracker, and discussions forum, providing multiple channels for questions and problem-solving. Development activity shows consistent attention to bug reports and feature requests from the community. The codebase remains actively maintained with updates addressing compatibility and reliability concerns raised by users.
