Sigil is a free, open source, multi-platform ebook editor that uses Qt (and QtWebEngine). It is designed to edit books in ePub format (both ePub 2 and ePub 3).

Sigil was designed to make it easy to create great ebooks using the EPUB format. If you are formatting books for your own use, or you are a professional editor publishing books on multiple platforms, then Sigil is for you. You can use Sigil to format and package your books into an EPUB that looks exactly the way you want it to using an advanced set of features that have made Sigil one of most popular EPUB editors available.

This open-source and completely free software is written and supported entirely by volunteers. The current Sigil development team includes Doug Massay and Kevin Hendricks as co-lead developers and maintainers. Previous developers/authors include John Schember, Grant Drake and Dave Heiland. Sigil was originally created by Strahinja Markovic in 2009 and remains completely free to download and use. Support is also provided by other volunteers who contribute code, translations and helpful answers to user's questions. See the Help=>About menu in Sigil for a complete list of contributors.

Features

  • Free and open source software under GPLv3
  • Multi-platform: runs on Windows, Linux and Mac
  • Full UTF-16 support
  • Full EPUB 2 spec support
  • Multiple Views: Book View, Code View and Preview View
  • WYSIWYG editing in Book View
  • Complete control over directly editing EPUB syntax in Code View
  • Table of Contents generator with multi-level heading support
  • Metadata editor with full support for all possible metadata entries (more than 200) with full descriptions for each
  • User interface translated into many languages
  • Spell checking with default and user configurable dictionaries
  • Full Regular Expression (PCRE) support for Find & Replace
  • Supports import of EPUB and HTML files, images, and style sheets,
  • Documents can be validated for EPUB compliance with the integrated FlightCrew EPUB validator
  • Embedded HTML Tidy: all imported files have their formatting corrected, and your editing can be optionally cleaned

What's New

Bug Fixes

  • Make sure assigned clip number is not editable in ClipEditor
  • Greatly speed up All Files report generation in epub3s with manifest properties
  • Greatly speed up Delete Used Media by caching current cover image
  • Greatly speed up adding bulk resources to the OPF to speed up Add Existing ...
  • Fix bug in Open With on MacOS not properly parsing arguments
  • Fix bug in refreshing plugin toolbars (Thank you BeckyEbook)
  • Fix bug in GetInfo not using the proper times symbol (Thanks BeckyEbook)
  • Fix stripping out of css selectors with non properites (empty)
  • Use resizeColumnsToContents to set DeleteUnunsedMedia and DeleteUnusedStyles column width
  • Prevent user created custom metadata elements from breaking the lxml parser badly (Thanks BeckyEbook)
  • Fix bug that stripped out custom etadata from epub before a save
  • Use more standard shortcuts for for Previous and Next tab
  • Stop Sigil tools from implicitly adding back nav to spine if not present

New Features

  • Create a separate Change Reading Order dialog for those who can not use drag and drop
  • Create a Drop Zone for users who want to use drag and drop to add files to their epub
  • Rewrite ImageTab to allow for basic image adjustments: rotate right, rotate left, crop, resize
  • Allow users more control over Prettify using prettyprint.xml created in Sigil prefs.
  • Update all CI github actions to the latest versions
  • Add cability to de-nest the newly native nested CSS so that it will work with e-readers
  • In ImageViewer move image description to the top (Thank you BeckyEbook)
  • Make ImageView open images fitted to its window automatically (Thanks BeckyEbook)
  • Recognize more core mediatypes for image/jxl and imaage/avif from epub 3.4 spec
  • Recognize json as a mediatype in Sigil in prep for epub 3.4 spec (Thanks drmhessler)
  • Support json syntax highlighting in CodeView to support epub 3.4 spec (Thanks drmhessler)
  • Add new epb3 tool menu items to safely add and remove the nav from the OPF spine