EPUB Conversion: EPUB Table of Contents (NCX) Preparation
The EPUB Table of Contents (TOC) is a component in the EPUB file with the technical name of Navigation Control file for XML or NCX. This article explains what an NCX is, how we create it for you during conversion, and how to format your manuscript to generate a perfect NCX that your readers and our retail distribution partners will love!
What is an NCX?
eReading devices utilize the navigation functions built into an EPUB file to move around the eBook. 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.
Figure 1: eBook NCX (TOC) displaying Headings 1, 2, and 3
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.
Now that you know about the technology, we will simply refer to the NCX file as the EPUB Table of Contents (TOC) from this point forward.
How the EPUB Table of Contents is Generated
Our converter scans your document for Heading 1, Heading 2, and Heading 3 styles and creates an entry in the EPUB Table of Contents (TOC) each time one of these styles is detected in your manuscript. Since an electronic TOC will be generated for your eBook, you should remove any TOC pages from your manuscript prior to uploading it to the EPUB converter.
NOTE: If your manuscript includes a TOC page with hyperlinks to chapters, the hyperlinks will not function following conversion; therefore if you plan to keep the TOC pages, we suggest you remove the hyperlinks as well as page numbers – since eBooks do not have pages in the traditional sense.
Prepare Your Manuscript to Create a Perfect EPUB Table of Contents (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 (TOC). This means each chapter and section must have a corresponding entry in the TOC.
For Example, let’s assume your book has a few main sections (Title Page, Copyright, Preface, Body, Epilogue) and a number of chapters, some of which contain subchapters or subsections. Your EPUB TOC will therefore consist of three levels:
- Apply Heading 1 style to the Title and to each line containing a Section name (copyright, prologue, etc.) or section (Part 1, Section II, etc.). Heading 1 style will always appear at the top of the next page.
- Apply Heading 2 style to each line containing a Chapter name or number
- Apply Heading 3 style to each line containing a subchapter or subsection.
IMPORTANT: Lulu supports a maximum of three levels in the EPUB Table of Contents (TOC). Do not use additional Heading styles (Heading 4, Heading 5) to denote chapter or section breaks, as these will not generate TOC entries. Readers will not be able to navigate to these chapters resulting in our retail distribution partners rejection of your eBook.
To prevent errors during conversion, Headings must be applied sequentially (Heading 1 > Heading 2 > Heading 3). You may use multiples of the same headings such as this sequence 1, 1, 1, 2, 2, 3, 2, 3, 3: however you cannot skip from 1 to 3.
TIP: If you are uploading multiple files for conversion to EPUB format, such as a separate file for each section or chapter, EACH file must include Heading 1 style on the first line (Introduction, Chapter 1, Chapter 2, etc.), otherwise you will receive an error message during conversion. Additionally, heading styles in EACH file must progress sequentially from Heading 1 > 2 > 3.
One of the top 10 reasons eBooks are rejected for distribution is an incomplete table of contents. Following the conversion of your manuscript to EPUB format, your eBook table of contents will be displayed. Please confirm all sections and chapters are listed. If you are missing entries, edit and re-upload your manuscript file(s) before progressing to the next step in the publishing process.