Sigil
What it is
Sigil is a free, open-source EPUB editor for creating and formatting ebooks on Linux, macOS, and Windows. It works with EPUB 2 and EPUB 3, offering Code View and Preview View for editing. Users can modify EPUB syntax directly and generate multilevel tables of contents from headings. The application imports EPUB and HTML files, images, and style sheets, then provides tools to mend or prettify imported material. Spell checking supports configurable dictionaries, while Find & Replace accepts regular expressions. EPUB export and ebook validation are included. Third-party plugins are supported, although plugins not written by Sigil developers are not vetted by them. Downloads include Windows x64, macOS Intel and Arm64, and a Linux AppImage. Windows installation requires version 10 1809 or newer, and current Sigil requires macOS 13 or newer. The former Book View WYSIWYG editor was removed; PageEdit can be opened separately through Sigil.
For and against
For
- Free and open source under GPLv3
- Supports EPUB 2 and EPUB 3
- Imports EPUB, HTML, images, and stylesheets
- Includes validation and table-of-contents tools
- Runs on Linux, macOS, and Windows
Against
- No free trial because the software is already free
- Former Book View editor was removed
- Windows requires version 10 1809 or newer
- Current macOS builds require macOS 13 or newer
The verdict
Sigil provides detailed EPUB editing, import, validation, and formatting tools without a license charge. Users should account for operating-system requirements and use PageEdit separately when they need the former WYSIWYG workflow.
Who it suits
Sigil suits personal ebook formatting and professional editors publishing across multiple platforms. It is useful for users who want direct EPUB editing on desktop operating systems.
Plans and prices
Sigil
Completely free to download and use · Windows, macOS, Linux
Read 3 Oct 2026 · sigil-ebook.com
On the record
- Audience
- The project describes Sigil as suitable for personal ebook formatting and professional editors publishing on multiple platforms.sigil-ebook.com · read 3 Oct 2026
- Download integrity
- Release files have automatically generated SHA-256 checksums available on the GitHub releases page.sigil-ebook.com · read 3 Oct 2026
- Editing features
- It offers Code View and Preview View, direct EPUB syntax editing, and a table of contents generator with multi-level heading support.sigil-ebook.com · read 3 Oct 2026
- EPUB support
- Sigil supports EPUB 2 and EPUB 3 specifications.sigil-ebook.com · read 3 Oct 2026
- Import and cleanup
- Sigil supports importing EPUB and HTML files, images, and style sheets, and can mend or prettify imported files.sigil-ebook.com · read 3 Oct 2026
- License
- Sigil is free and open source under GPLv3.sigil-ebook.com · read 3 Oct 2026
- Operating systems
- The download page lists Windows x64 and macOS Intel and Arm64 downloads, and offers a Linux AppImage.sigil-ebook.com · read 3 Oct 2026
- Plugins
- Sigil supports third-party plugins, which may be open source or proprietary and are not vetted by Sigil developers unless a developer authored them.sigil-ebook.com · read 3 Oct 2026
- Purpose
- Sigil is an EPUB editor designed to help users create and format ebooks.sigil-ebook.com · read 3 Oct 2026
- Release signing
- Since Sigil v0.9.9, Git tags and source archives used for releases are signed with Doug Massay’s PGP key.sigil-ebook.com · read 3 Oct 2026
- Search and spelling
- Sigil includes spell checking with configurable dictionaries and regular expression support for Find & Replace.sigil-ebook.com · read 3 Oct 2026
- Support
- The official user support forum is on MobileRead, and the developers say direct support emails will almost always go unanswered because this is a volunteer community project.sigil-ebook.com · read 3 Oct 2026
- Version requirements
- The Windows installer requires Windows 10 version 1809 or newer, and current Sigil requires macOS 13 or newer.sigil-ebook.com · read 3 Oct 2026
- WYSIWYG editing
- Sigil’s former Book View WYSIWYG editor was removed; the separate PageEdit application can be launched through Sigil’s Open With feature or external editor button.sigil-ebook.com · read 3 Oct 2026
