Jellyfin, the free and open-source media server, has released version 12.0. The first thing longtime users will notice is the version number.
What was previously Jellyfin 10.12 is now simply Jellyfin 12.0, with the project dropping the largely meaningless leading “10” from its versioning scheme. Jellyfin 10.11.x was the final branch to use the old format.
Under the hood, much of the work in Jellyfin 12.0 builds on the database overhaul introduced with 10.11. Playlists, collections, and boxsets are now stored so the database can work with individual entries instead of repeatedly loading entire lists. As a result, large playlists should be noticeably faster.
Another notable addition is support for multiple versions of TV episodes. Different editions or resolutions of the same episode (for example, 1080p and 4K copies) can now be grouped together in the same way Jellyfin already handles alternate movie versions.
This release also gives books and comics more attention. Much of the functionality previously supplied by the Bookshelf plugin has moved directly into Jellyfin Server, including metadata extraction from OPF and ComicInfo files, generated covers for EPUBs and comic archives, page counts for comics and PDFs, audiobook chapter extraction, and improved filename parsing.
The web client complements those backend changes with a Modern book library layout, redesigned reading interface, improved EPUB font-size controls, progress indicators, and author-focused browsing. The old Bookshelf plugin is deprecated.
On the UI side, Jellyfin’s previously experimental Modern layout is now the default on desktop and mobile installations unless the user has selected something else. The former interface remains available under the new “Legacy” name, while TV devices continue using their existing TV layout.
Search and recommendations are becoming more extensible as well. Plugins can now contribute their own search results and recommendation data, while recommendation providers can be selected separately for individual libraries. ListenBrainz is included as one such source for music recommendations.
For media handling, Jellyfin 12.0 moves to FFmpeg 8.1 and includes improvements around CUDA transposing, OpenCL scaling and tone mapping, Dolby Vision compatibility, subtitles, AV1 direct streaming on TV clients, and playback support across webOS, Tizen, Android TV, and iOS.
The release also contains several security fixes covering issues such as crafted requests accessing files outside intended directories, cross-site scripting vulnerabilities in the web client, unsafe plugin package names, and weaknesses involving the setup wizard and parental controls.
Finally, keep in mind some important upgrade requirements. Jellyfin 12.0 changes the database schema and rewrites data during the first startup, so users should make a full backup before upgrading. Systems must already run Jellyfin 10.10.7 or any 10.11.x release, and a full library scan is required afterward.
Additionally, third-party plugins built for Jellyfin 10.11 will need updated versions to work with 12.0, and some very old clients relying on deprecated /emby/ or /mediabrowser/ endpoints will stop functioning.
For more details, refer to the official Jellyfin 12.0 release announcement.
