How to create the "container.xml" file of an EPUB 3.1 book?

The "container.xml" file of an EPUB 3.1 book is a required file in the book ZIP container. It specifies a package file of any name, for example: package.opf.

Here is the requirement on the "container.xml" file:

1. The "container.xml" file must be named as "container.xml".

2. The "container.xml" file must be an XML file and meet the EPUB Open Container Format (OCF) 3.1 specifications.

3. The "container.xml" file must specify at least 1 package file, any name, for example: package.opf.

4. The "container.xml" file must be placed in a sub-directory called META-INF of the EPUB 3.1 book ZIP container.

You can create the "container.xml" file with any text editor. Here is an example:

<?xml version="1.0" encoding="utf-8"?>
<container xmlns="urn:oasis:names:tc:opendocument:xmlns:container" version="1.0">
  <rootfiles>
    <rootfile full-path="package.opf" media-type="application/oebps-package+xml"/>
  </rootfiles>
</container>

Download Hello-3.1.epub, and unzip it. You see an example of "container.xml" in the META-INF directory.

⇒ Hello-3.1.epub - Package File: package.opf

⇐ Hello-3.1.epub - "mimtype" File

⇑ Introduction of EPUB 3.1 Specification

⇑⇑ EPUB Tutorials