head to head · open source
koreader vs calibre-web
koreader has 29,761 GitHub stars, 1,908 forks, 1,345 open issues and last shipped yesterday. calibre-web has 18,198 stars, 1,860 forks, 409 open issues and last shipped 13 days ago. koreader leads on adoption by 64% (29,761 vs 18,198 stars). koreader is written in Lua under AGPL-3.0; calibre-web is written in Fluent under GPL-3.0. koreader has attracted 6% as many forks as stars, calibre-web 10%. koreader was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 2 topic tags (ebook, epub), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
← all 8884 open source comparisons
Side by side
| koreader | calibre-web | |
|---|---|---|
| GitHub stars | ★ 30K | ★ 18K |
| License | AGPL-3.0 | GPL-3.0 |
| Written in | Lua | Fluent |
| Last push | 2026-09-17 | 2026-09-05 |
| Forks | ⑂ 1.9K | ⑂ 1.9K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick koreader if
- You weight community size — 30K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Lua
- You value the larger contributor base for long-term maintenance
pick calibre-web if
- You want the calibre-web feature set and don't need the biggest community
- You prefer the GPL-3.0 license terms
- Your stack matches Fluent
- You evaluated both and calibre-web fits your workflow better
About koreader
KOReader is a free, AGPL 3.0 licensed document viewer written in Lua that runs on e ink readers from Cervantes, Kindle, Kobo and PocketBook, on reMarkable, and on Android and desktop Linux, aimed at readers who want broader format support, finer typesetting control and better performance than the reading software shipped with their device.
read the full koreader overview →
About calibre-web
Calibre Web is a web application that provides a clean and intuitive interface for browsing, reading, and downloading eBooks from a valid Calibre database. It is a fork of the library project (calibreserver) and is licensed under the GPL v3. The project lives in the Calibre ecosystem, and it is distributed through PyPI as the calibreweb package as well as through Docker images. It has been developed for over eleven years and carries roughly 18,183 stars and 1,856 forks on GitHub.
read the full calibre-web overview →
More in Content & Publishing
Related comparisons
More Publishing projects
Compare either of these against the rest of the Publishing field.
Frequently asked questions
Is koreader or calibre-web more popular?
koreader has 29,761 GitHub stars and calibre-web has 18,198. koreader has the larger community by that measure.
Are koreader and calibre-web free?
Both are open source. koreader is licensed under AGPL-3.0 and calibre-web under GPL-3.0. Neither carries a licence fee.
What is the difference between koreader and calibre-web?
koreader is written in Lua and calibre-web in Fluent. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, koreader or calibre-web?
Choose koreader if you want the larger community (29,761 stars) or its AGPL-3.0 licence terms. Choose calibre-web if its feature set, stack or GPL-3.0 licence fits better. Both are self-hostable.