The EPUB Table of Contents is a component in the EPUB called the NCX file. The purpose of this article is to explain what an NCX is, how we create it for you, and how to format your eBook to generate a perfect NCX that your readers and our retail distribution partners will love!
What is an NCX?
e-readers use navigation built into your EPUB to allow readers to move around in your book. This navigation is specified in the Navigation Control file for XML (NCX). An NCX with multiple chapters is required to distribute your eBook to our retail distribution partners. Lulu’s EPUB Converter will create the NCX for you, but we need to know where each chapter begins. Our converter does this by looking for Heading styles in your document.
How the NCX is Generated
Our converter scans your document for Word’s Heading 1, Heading 2, and Heading 3 styles and creates an entry in the EPUB Table of Contents (NCX) each time one of these styles is used.
Preparing Your File to Make a Perfect NCX
Our retail distribution partners require you to provide a way for readers to navigate to every major section of your eBook via the EPUB Table of Contents (NCX). This means you must map each chapter and section to a corresponding entry in the NCX.
Let’s assume your book has a few main sections and a bunch of chapters, some of which contain subchapters or subsections. You must create a 3-level EPUB Table of Contents:
- Apply the Heading 1 style to each line containing a Section name or number.
- Apply the Heading 2 style to each line containing a Chapter name or number
- Apply the Heading 3 style to each line containing a subchapter or subsection.
IMPORTANT: We support a maximum of three levels in the EPUB Table of Contents. Do not use additional Heading styles (Heading 4, Heading 5) to denote chapter or section breaks, as these will not generate NCX entries. Readers will not be able to easily navigate to these chapters, and our retail distribution partners will reject your eBook.
