KOReader: a document viewer primarily aimed at e-ink readers (31k stars)
What it does
All text below is quoted directly from the project README.
>An ebook reader application supporting PDF, DjVu, EPUB, FB2 and many more formats, running on Cervantes, Kindle, Kobo, PocketBook and Android devices
Main features:
- portable: runs on embedded devices (Cervantes, Kindle, Kobo, PocketBook, reMarkable), Android and Linux computers. Developers can run a KOReader emulator in Linux and MacOS.
- multi-format documents: supports fixed page formats (PDF, DjVu, CBT, CBZ) and reflowable e-book formats (EPUB, FB2, Mobi, DOC, RTF, HTML, CHM, TXT). Scanned PDF/DjVu documents can also be reflowed with the built-in K2pdfopt library. ZIP files are also supported for some formats.
- full-featured reading: multi-lingual user interface with a highly customizable reader view and many typesetting options. You can set arbitrary page margins, override line spacing and choose external fonts and styles. It has multi-lingual hyphenation dictionaries bundled into the application.
- integrated with calibre (search metadata, receive ebooks wirelessly, browse library via OPDS), Wallabag, Wikipedia, Google Translate and other content providers.
- optimized for e-ink devices: custom UI without animation, with paginated menus, adjustable text contrast, and easy zoom to fit content or page in paged media.
- extensible: via plugins
- fast: on some older devices, it has been measured to have less than half the page-turn delay as the built in reading software.
- and much more: look up words with StarDict dictionaries / Wikipedia, add your own online OPDS catalogs and RSS feeds, over-the-air software updates, an FTP client, an SSH server, …
>Please follow the model specific steps for your device: Android, Cervantes, Kindle, Kobo, Linux, Pocketbook, reMarkable
Repository
koreader/koreader
Repository stats
|Metric|Value|
|:-|:-|
|Stars|30,636|
|Forks|2.0k|
|Last release|v2026.07.1 (2026-08-01)|
|Languages|Lua 97.1%, Shell 2.4%, Python 0.2%|
|Contributors|415|
|AI contributor accounts (Claude / Codex / Cursor / Copilot)|@claude (7 commits)|
|AI co-authored commits|Claude: 7|
Main contributor
|Field|Value|
|:-|:-|
|Name|QP Hou|
|GitHub|@houqp|
|Commits to this repo|1,760 (top contributor)|
|Company / Location|Bay|
|Followers|536|
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78 points · 1 comment
Mentions
KOReader: a document viewer primarily aimed at e-ink readers (31k stars) What it does All text below is quoted directly from the project README. >An ebook reader application supporting PDF, DjVu, EPUB, FB2 and many more formats, running on Cervantes, Kindle, Kobo, PocketBook and Android devices Main features: - portable: runs on embedded devices (Cervantes, Kindle, Kobo, PocketBook, reMarkable), Android and Linux computers. Developers can run a KOReader emulator in Linux and MacOS. - multi-format documents: supports fixed page formats (PDF, DjVu, CBT, CBZ) and reflowable e-book formats (EPUB, FB2, Mobi, DOC, RTF, HTML, CHM, TXT). Scanned PDF/DjVu documents can also be reflowed with the built-in K2pdfopt library. ZIP files are also supported for some formats. - full-featured reading: multi-lingual user interface with a highly customizable reader view and many typesetting options. You can set arbitrary page margins, override line spacing and choose external fonts and styles. It has multi-lingual hyphenation dictionaries bundled into the application. - integrated with calibre (search metadata, receive ebooks wirelessly, browse library via OPDS), Wallabag, Wikipedia, Google Translate and other content providers. - optimized for e-ink devices: custom UI without animation, with paginated menus, adjustable text contrast, and easy zoom to fit content or page in paged media. - extensible: via plugins - fast: on some older devices, it has been measured to have less than half the page-turn delay as the built in reading software. - and much more: look up words with StarDict dictionaries / Wikipedia, add your own online OPDS catalogs and RSS feeds, over-the-air software updates, an FTP client, an SSH server, … >Please follow the model specific steps for your device: Android, Cervantes, Kindle, Kobo, Linux, Pocketbook, reMarkable Repository koreader/koreader Repository stats |Metric|Value| |:-|:-| |Stars|30,636| |Forks|2.0k| |Last release|v2026.07.1 (2026-08-01)| |Languages|Lua 97.1%, Shell 2.4%, Python 0.2%| |Contributors|415| |AI contributor accounts (Claude / Codex / Cursor / Copilot)|@claude (7 commits)| |AI co-authored commits|Claude: 7| Main contributor |Field|Value| |:-|:-| |Name|QP Hou| |GitHub|@houqp| |Commits to this repo|1,760 (top contributor)| |Company / Location|Bay| |Followers|536| ────────────────────────────── 📌 How many great GitHub repos have you discovered and completely forgotten about? Don't let another useful tool disappear into your Reddit feed. Get the community's best repos, organized by category, plus key takeaways from real developer discussions, delivered to your inbox twice a week. 📬 Never lose track of great repos again. Subscribe free.