Software update: Caliber 4.6.0

The sixth update for version 4.0 of Caliber has been released. Caliber is an open source ebook management program and is available for Windows, Linux and macOS. Among other things, it can look up all relevant information and cover images, and convert ebooks to make them suitable for the various types of e-readers. Furthermore, the program can convert newspapers, magazines and news articles based on RSS feeds into e-book format. With Caliber, books can also be purchased from well-known web stores. In version 4.0 we find a completely renewed Content Server, there is a new e-book viewer and Qt WebKit has been replaced by Qt WebEngine. In version 4.6.0 we find, among other things, a dark mode.

New features

  • Windows 10: Add support for the dark mode.
    If you turn on dark mode under the Windows Settings-> Personalization-> Colors and restart caliber it will use dark colors. Can also be enabled by setting the CALIBRE_USE_DARK_PALETTE environment variable.
  • Polish books tool: Add a setting to add or remove soft hyphens from the book text
  • Viewer: Re-enable the old reference mode from caliber 3.x

Bug fixes

  • PDF Output: Fix the option to break long words at the end of lines not working since caliber 4. Closes tickets: 1854349
  • DOCX Input: Fix incorrect font sizes for footnote references in paragraphs that have text with multiple font sizes. 1855403
  • DOCX Input: Avoid nested tags for footnote references
  • Viewer: Fix max text width / height settings not being applied correctly on window resize. Closes tickets: 1854211
  • Viewer: Auto-expand entries in the Table of Contents when viewing the corresponding location in the book.
  • Viewer: When creating a new bookmark, if there is selected text use it as the default bookmark title. Closes tickets: 1854611

Version number 4.6.0
Release status Final
Operating systems Windows 7, Linux, macOS, Windows Vista, Windows 8, Windows 10
Website Caliber
File size


License type GPL