Calibre-Web

What is Calibre-Web?

Calibre-Web is an open source web application that puts a clean reading and browsing interface on top of an existing Calibre ebook library. You point it at your Calibre database and it serves your books to any browser — search, read in-page, edit metadata, and download or send titles to your e-reader, all self-hosted on your own server.

What is Calibre-Web best for?

Calibre-Web is best for people who already keep their ebooks in Calibre and want to reach that library from anywhere without opening the Calibre desktop app. It suits home-server owners and small households who want a multi-user, Jellyfin-style front end for books, with per-user permissions and shelves.

What can Calibre-Web do?

• Browse, search, and filter your library with detailed metadata filters (author, tag, series, language, rating)
• Read EPUB, PDF, comics (CBR/CBZ), DjVu, TXT, FB2, and MP3 audiobooks directly in the browser
• Serve an OPDS feed so e-reader apps like Moon+ Reader, KOReader, and Marvin can connect
• Send books to Kindle and Kobo devices, converting formats on the fly via Calibre’s tools
• Sync natively with Kobo e-readers and use “Magic Link” login for devices that can’t type passwords
• Manage multiple users with granular permissions, plus LDAP, OAuth (Google/GitHub), and proxy auth
• Edit metadata and covers, and upload new books through the web UI

Where does Calibre-Web fall short?

• It reads an existing Calibre database but can’t build one from scratch — you still need Calibre (or a fork) to import and organize new books before they appear.
• Format conversion and cover extraction lean on external binaries (the Calibre tools, ImageMagick, Ghostscript on Windows), so send-to-Kindle and some features won’t work until those are installed.
• Library performance degrades on very large collections — users report slowdowns past roughly 20,000 books.
• Active development has slowed; a community fork, Calibre-Web-Automated, adds automated ingest and is where much of the momentum now sits.

Is Calibre-Web free?

Yes — Calibre-Web is completely free and open source under the GPL-3.0 license. There is no paid tier, no cloud subscription, and no per-user cost. You only pay for the server or device you run it on, which for most people is an existing home server, NAS, or Raspberry Pi.

What does Calibre-Web replace?

Calibre-Web is a self-hosted stand-in for the cloud reading libraries of Amazon Kindle, Google Play Books, and Apple Books. Instead of renting access to books inside a vendor’s ecosystem, you own the files, host them yourself, and read them on any device. It overlaps with other self-hosted book servers like Kavita, which manages its own library rather than reading a Calibre one.

FAQ

Is Calibre-Web open source? Yes. Calibre-Web is licensed under GPL-3.0, and the full source is on GitHub. It is genuine OSI-approved open source, not source-available.

Can I self-host Calibre-Web for free? Yes. Self-hosting is the only way it runs, and the software costs nothing — you provide the server. It ships as a Docker image and as a Python package, so it runs comfortably on a NAS, mini PC, or Raspberry Pi.

Do I need Calibre installed to use Calibre-Web? You need a Calibre library (a folder with a metadata.db), which the Calibre desktop app creates. You don’t need Calibre running alongside the server, but installing the Calibre binaries enables format conversion and send-to-Kindle.

Is Calibre-Web a good Kindle alternative? For reading and organizing books you already own, yes — it keeps your library private and reachable from any browser or e-reader. It isn’t a bookstore, so you buy or source books elsewhere and add them to Calibre.