Convert EPUB to AsciiDoc

Why Convert EPUB to AsciiDoc?

Converting EPUB e-books to AsciiDoc format is essential for authors, technical writers, and publishers who need to edit, update, or repurpose existing e-book content. While EPUB is excellent for distribution and reading, AsciiDoc provides a powerful authoring environment that integrates seamlessly with modern documentation workflows and version control systems.

AsciiDoc is the preferred format for technical book publishing, particularly with O'Reilly Media's Atlas publishing platform. By converting EPUB to AsciiDoc, you gain access to features like automatic table of contents generation, cross-references, code syntax highlighting, admonition blocks (notes, warnings, tips), and the ability to include content from external files. This makes maintaining and updating large documents significantly easier.

One of the key advantages of AsciiDoc over EPUB for authoring is version control compatibility. Since AsciiDoc files are plain text, they work perfectly with Git and other version control systems. This enables collaborative authoring, change tracking, branching for different editions, and easy merging of contributions from multiple authors - workflows that are nearly impossible with binary EPUB files.

The conversion process extracts the structured content from EPUB (chapters, headings, paragraphs, lists, code blocks) and transforms it into clean AsciiDoc markup. While some complex visual formatting may need manual adjustment, the core content structure is preserved, giving you a solid foundation for further editing and enhancement.

Key Benefits of Converting EPUB to AsciiDoc:

• Editable Source: Plain text format for easy editing and updates
• Version Control: Works with Git for collaborative authoring
• Multi-format Output: Generate HTML, PDF, EPUB, DocBook from single source
• Technical Features: Code highlighting, admonitions, includes
• O'Reilly Publishing: Native format for Atlas platform
• Documentation Systems: Integrates with Antora, Jekyll, Hugo
• Modular Content: Split into chapters, include external files

Practical Examples

Example 1: Chapter Conversion

Input EPUB content (chapter1.xhtml):

<h1>Getting Started</h1>
<p>Welcome to <strong>Python Programming</strong>.
This guide will help you learn the basics.</p>
<h2>Installation</h2>
<p>First, download Python from the official website.</p>
<pre><code>python --version</code></pre>

Output AsciiDoc file (chapter1.asciidoc):

= Getting Started

Welcome to *Python Programming*.
This guide will help you learn the basics.

== Installation

First, download Python from the official website.

[source,bash]
----
python --version
----

Example 2: Technical Book Structure

Input EPUB table of contents:

Book: Web Development Guide
├── Part I: Frontend
│   ├── Chapter 1: HTML Basics
│   ├── Chapter 2: CSS Styling
│   └── Chapter 3: JavaScript
└── Part II: Backend
    ├── Chapter 4: Node.js
    └── Chapter 5: Databases

Output AsciiDoc book structure:

= Web Development Guide
:toc: left
:toclevels: 3
:sectnums:

= Part I: Frontend

include::chapters/ch01-html.asciidoc[]
include::chapters/ch02-css.asciidoc[]
include::chapters/ch03-javascript.asciidoc[]

= Part II: Backend

include::chapters/ch04-nodejs.asciidoc[]
include::chapters/ch05-databases.asciidoc[]

Example 3: Code and Admonitions

Input EPUB with code blocks:

<div class="note">
  <p>Important: Always backup your data.</p>
</div>
<pre class="python">
def hello():
    print("Hello, World!")
</pre>

Output AsciiDoc with admonitions:

NOTE: Always backup your data.

[source,python]
----
def hello():
    print("Hello, World!")
----

Frequently Asked Questions (FAQ)

Q: What is AsciiDoc?

A: AsciiDoc is a lightweight markup language for writing technical documentation, articles, books, and more. It's similar to Markdown but more powerful, with support for complex tables, admonitions, cross-references, and includes. Files use .asciidoc, .adoc, or .asc extensions. The main processor is Asciidoctor (Ruby-based).

Q: What's the difference between AsciiDoc and ADOC?

A: They're the same thing! ADOC is just a common file extension for AsciiDoc files. You might see .adoc, .asciidoc, or .asc - all are valid extensions for AsciiDoc documents. The format and syntax are identical regardless of which extension you use.

Q: Will images be preserved in the conversion?

A: The conversion extracts image references and creates proper AsciiDoc image macros (image::path/to/image.png[]). However, the actual image files are embedded in the EPUB archive and may need to be extracted separately. Our converter handles the text content and image references; you may need to export images from the EPUB manually for complete documents.

Q: Can I convert AsciiDoc back to EPUB?

A: Yes! That's one of AsciiDoc's strengths. Using Asciidoctor with the asciidoctor-epub3 extension, you can generate EPUB3 files from AsciiDoc source. This enables a workflow where you maintain your book in AsciiDoc and publish to multiple formats including EPUB, PDF, and HTML from a single source.

Q: Why is AsciiDoc preferred for technical books?

A: AsciiDoc offers features essential for technical writing: syntax-highlighted code blocks, admonition blocks (NOTE, TIP, WARNING, CAUTION, IMPORTANT), cross-references between sections, automatic numbering, includes for modular content, and variables/attributes. It's the native format for O'Reilly's publishing platform and works well with documentation systems like Antora.

Q: How does AsciiDoc compare to Markdown?

A: AsciiDoc is more powerful than Markdown for complex documents. While Markdown is simpler and more widely known, AsciiDoc supports tables with merged cells, admonitions, includes, conditional content, custom attributes, automatic TOC generation, and built-in support for technical documentation features. For simple documents use Markdown; for books and technical docs, AsciiDoc is often better.

Q: What tools can I use to edit AsciiDoc files?

A: Any text editor works since AsciiDoc is plain text. Popular choices include: VS Code with AsciiDoc extension (live preview), IntelliJ IDEA with AsciiDoc plugin, Atom with asciidoc-preview, Sublime Text, and Vim/Neovim. For preview and conversion, install Asciidoctor (Ruby gem) or use the Asciidoctor.js browser extension.

Q: Can I use AsciiDoc with Git for version control?

A: Absolutely! This is one of AsciiDoc's major advantages. Since files are plain text, Git can track changes line-by-line, show meaningful diffs, enable branching for different editions, and merge contributions from multiple authors. Many technical books and documentation projects use Git + AsciiDoc workflows. Platforms like GitHub and GitLab even render AsciiDoc files directly.