koreader – koreader

<img src="https://raw.githubusercontent.com/koreader/koreader.github.io/master/koreader-logo.png" alt="KOReader" class="ra0-md-img" loading="lazy" />

KOReader is a document viewer primarily aimed at e-ink readers.

[![AGPL Licence][badge-license]](COPYING)
[![Latest release][badge-release]][link-gh-releases]
[![Gitter][badge-gitter]][link-gitter]
[![Mobileread][badge-mobileread]][link-forum]
[![Build Status][badge-circleci]][link-circleci]
[![Coverage Status][badge-coverage]][link-coverage]
[![Weblate Status][badge-weblate]][link-weblate]

Download •
User guide •
Wiki •
Developer docs

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][link-wiki-zip] 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 check the user guide and the [wiki][link-wiki] to discover more features and to help us document them.

Screenshots

Installation

Please follow the model specific steps for your device:

Android •
Cervantes •
Kindle •
Kobo •
Linux •
Pocketbook •
reMarkable

Development

Setting up a build environment •
Collaborating with Git •
Building targets •
Porting •
Developer docs

Support

KOReader is developed and supported by volunteers all around the world. There are many ways you can help:

• [fix bugs][link-issues-bugs] and [implement new features][link-issues-features]
• [translate the program into your language][link-weblate] or improve an existing translation
• document lesser-known features on the [wiki][link-wiki]
• help others with your knowledge on the [forum][link-forum]

Right now we only support liberapay donations.

Contributors

[![Last commit][badge-last-commit]][link-gh-commits]
[![Commit activity][badge-commit-activity]][link-gh-insights]

[badge-bountysource]:https://img.shields.io/bountysource/team/koreader/activity?color=red
[badge-circleci]:https://circleci.com/gh/koreader/koreader.svg?style=shield
[badge-coverage]:https://codecov.io/gh/koreader/koreader/branch/master/graph/badge.svg
[badge-commit-activity]:https://img.shields.io/github/commit-activity/m/koreader/koreader
[badge-gitter]:https://img.shields.io/gitter/room/koreader/koreader?color=red
[badge-last-commit]:https://img.shields.io/github/last-commit/koreader/koreader?color=orange
[badge-license]:https://img.shields.io/github/license/koreader/koreader
[badge-release]:https://img.shields.io/github/release/koreader/koreader.svg
[badge-mobileread]:https://img.shields.io/badge/forum-on_mobileread-lightgrey
[badge-weblate]:https://hosted.weblate.org/widgets/koreader/-/koreader/svg-badge.svg

[link-bountysource]:https://www.bountysource.com/teams/koreader
[link-circleci]:https://circleci.com/gh/koreader/koreader
[link-coverage]:https://codecov.io/gh/koreader/koreader
[link-forum]:http://www.mobileread.com/forums/forumdisplay.php?f=276
[link-gh-commits]:https://github.com/koreader/koreader/commits/master
[link-gh-insights]:https://github.com/koreader/koreader/pulse
[link-gh-releases]:https://github.com/koreader/koreader/releases
[link-gitter]:https://gitter.im/koreader/koreader
[link-issues-bugs]:https://github.com/koreader/koreader/issues?q=is%3Aopen+is%3Aissue+label%3Abug
[link-issues-features]:https://github.com/koreader/koreader/issues?q=is%3Aopen+is%3Aissue+label%3Aenhancement
[link-weblate]:https://hosted.weblate.org/engage/koreader/?utm_source=widget
[link-wiki]:https://github.com/koreader/koreader/wiki
[link-wiki-zip]:https://github.com/koreader/koreader/wiki/ZIP