Viewing ePub on macOS with Calibre 10 April 2023

Calibre can serve as a stand-alone viewer app for ePub files on macOS.

Of course, ebook reading is possible on macOS by using Apple’s Books app in ePub and PDF formats. This brings its own file management, similarly to the handling of audio files in with the iTunes app’s library. While this entails adding ebook files to the Books library, it enables convenient iCloud syncing.

However, this does not lend itself for quickly viewing ebook files in-place. While PDF files can be opened in Apple’s Preview app, there is no viewer on macOS for in-place viewing of ePub files. To do so, a third party app is needed.

While trying various ebook viewers for macOS, I tested Aldiko, Calibre, FBReader 2.0, and Thorium Reader.

Altogether, I most enjoyed the viewer of Calibre. However, the ePub files cannot simply be opened in the Calibre viewer as I
intended. Instead, opening an ePub with Calibre adds this file to its library.

With a trick however, it is possible to bypass the Calibre library. Then, the viewer can be invoked directly: Hidden in the Calibre app package, there is an “”, to which ePub files can be associated with. This directly opens ePub files in Calibre’ viewer app.

A little more complication arises when upgrading Calibre to a new version: This can entail a dissociation of ePub files with the viewer app. This is avoided by creating an app with a symbolic link to /Applications/

  • write a shell script named consisting of
    /Applications/ $@
  • bundle the script to an app using the Python script mac-appify:
    1. install it using: pip install mac-appify
    2. run it with: appify,
    3. link the icon: ln -s /Applications/
  • can finally be removed again: rm is then ready for launching the Calibre viewer.

For Calibre’s ebook editor, this procedure is applicable as well, replacing the term “viewer” with “edit”.

Finally, let me mention that the Calibre viewer can also display many further formats, even PDF files, with the option to reformat it.