Sigil

Free plan LinuxMacWindows

What Sigil is

Sigil is a free, open-source editor for creating and formatting EPUB ebooks. It supports EPUB 2 and EPUB 3 on Linux, macOS, and Windows, and is licensed under GPLv3. Editors can switch between Code View and Preview View, edit EPUB syntax directly, and generate a table of contents with multiple heading levels. Sigil imports EPUB and HTML files, images, and style sheets, and can mend or prettify imported files. It also provides spell checking with configurable dictionaries and Find & Replace using regular expressions. Third-party plugins are supported, though plugins not authored by Sigil developers are not vetted by them. Downloads include Windows x64, macOS Intel and Arm64, and a Linux AppImage. The Windows installer requires Windows 10 version 1809 or newer, while current Sigil requires macOS 13 or newer. The former Book View WYSIWYG editor has been removed; PageEdit can be launched separately through Sigil. The volunteer project points users to its MobileRead support forum.

Who it suits

Sigil suits people formatting EPUB books, from personal projects to professional publishing workflows. It is a fit for users comfortable editing code or working in Preview View.

What it does well

Free and open source under GPLv3
Supports EPUB 2 and EPUB 3
Imports EPUB, HTML, images, and style sheets
Includes spell checking and regular-expression Find & Replace

What to know first

Current Sigil requires macOS 13 or newer
Windows installer requires Windows 10 version 1809 or newer
Former Book View WYSIWYG editor was removed

Plans

Plan	Billed and limits	Price
Sigil	Completely free to download and use · Windows, macOS, Linux	Free

As sigil-ebook.com lists them, read 3 Oct 2026. The maker's own page has the final word.

Getting started

Visit https://sigil-ebook.com/ to find the project’s downloads.
Choose the download for Windows x64, macOS Intel or Arm64, or Linux AppImage.
Check that Windows is version 10 1809 or newer, or macOS is version 13 or newer.
Install or run Sigil on the supported operating system.
Import EPUB or HTML files, images, or style sheets, or begin editing EPUB content.

Verdict

Sigil provides EPUB editing, import, and cleanup tools at no cost. Users seeking the former WYSIWYG Book View should know it has been removed; PageEdit is a separate option launched through Sigil.

Questions

How much does Sigil cost?

Sigil is free to download and use. Its listed plan is free.

Is Sigil open source?

Yes. Sigil is licensed under GPLv3.

Which operating systems does Sigil support?

Sigil supports Linux, macOS, and Windows. Downloads include Windows x64, macOS Intel and Arm64, and a Linux AppImage.

Which EPUB versions can I edit with Sigil?

Sigil supports the EPUB 2 and EPUB 3 specifications.

Does Sigil include a WYSIWYG editor?

Its former Book View WYSIWYG editor was removed. The separate PageEdit application can be launched from Sigil through Open With or the external editor button.

Where can users get support?

The official user support forum is on MobileRead. The developers say direct support emails will almost always go unanswered because the project is run by volunteers.

Facts from Sigil's own pages

Audience: The project describes Sigil as suitable for personal ebook formatting and professional editors publishing on multiple platforms. · sigil-ebook.com, 3 Oct 2026
Download integrity: Release files have automatically generated SHA-256 checksums available on the GitHub releases page. · sigil-ebook.com, 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, 3 Oct 2026
EPUB support: Sigil supports EPUB 2 and EPUB 3 specifications. · sigil-ebook.com, 3 Oct 2026
Founded: 2009 · sigil-ebook.com, 28 Sept 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, 3 Oct 2026
License: Sigil is free and open source under GPLv3. · sigil-ebook.com, 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, 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, 3 Oct 2026
Purpose: Sigil is an EPUB editor designed to help users create and format ebooks. · sigil-ebook.com, 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, 3 Oct 2026
Search and spelling: Sigil includes spell checking with configurable dictionaries and regular expression support for Find & Replace. · sigil-ebook.com, 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, 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, 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, 3 Oct 2026

Where Sigil stands on Freedom251

eBook Creation Software#17 of 28