dekay edited this page Oct 5, 2018 · 91 revisions



KOReader is a document viewer for E-ink devices. Supported document formats include PDF, DjVu, XPS, CBZ, FB2, PDB, TXT, HTML, RTF, CHM, EPUB, DOC, MOBI, and ZIP files. Latest Kindle and Kobo devices are supported. The original software stays available to use after installation.

  • reflow of complex PDF's using k2pdfopt
  • saving and exporting notes to files or Evernote
  • custom .ttf fonts and stardict dictionaries
  • cloud storage (Dropbox, FTP) and synchronization
  • content providers: Wikipedia, OPDS and Goodreads

An extended survey can be found on Features list or jump directly to Configuration, Community.

Getting started

First-time users need to setup a way to launch KOReader. Choose your device brand and follow the model specific steps on one of the following pages: Kindle, Kobo or Pocketbook. This brand-model separation stems from the highly device-specific tool-chains used.


Make sure that you have completed the preceding setup completely. Save the settings of any existing KOReader installation if necessary before upgrading. (Long pressing certain menu actions will save the program's defaults automatically to a separate file defaults.persistent.lua. See Change defaults for making manual changes.)

Using Wi-Fi

Assuming you already installed KOReader successfully. Enable Wi-Fi and connect to the internet. Use KOReader's top menu to check for a new version. You can to check for upgrades on predefined stable or nightly OTA channels.

Connected as a USB mass storage device

Choose the KOReader build archive appropriate for your device from the following channels:

  • nightly builds: generated automatically overnight. These builds sometimes contain severe bugs (tracked in issue tracker), but they also contain the latest daily patches.
  • stable builds: released every two months on average. Release notes are attached.
  • custom builds: build it by yourself.

Unpack the downloaded archive in the right folder on your device (see device specific setup instructions for finding the correct path) to install/upgrade.


After starting up KOReader, all you need to do is navigate the file manager to a (hidden) library folder and set it as default by long-pressing the file name. Files with supported file extensions will show up in this file manager. Touch gestures for navigating the user interface are explained in gestures. Read more about less known useful functions.

Development community

KOReader is rewrite of "kindlepdfviewer", which is originally built by hawhill based on the mupdf source. Since then it has come a long way, based on requests and updates by hackers around the world. The name "KOReader stands for Kindle/Kobo Open Reader, the devices for which KOReader originally was written.


Some of the content on the WIKI might be out of date. You are welcome to make it better by opening an issue if you find any of the instructions unclear or confusing.

You can open new issues on the issue tracker. There are related discussion threads on the MobileRead Forums, one of the largest English language web forums for e-book reading/publishing:


Contribute by writing code.

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