EPUB Table of Contents Not Working? How to Rebuild It

The table of contents is the most fragile part of an EPUB. The book opens, the chapters are all there — but the TOC is empty, lists "Chapter 1" five times, or jumps to the wrong page when tapped. Nothing is wrong with your chapters; the navigation file that indexes them has drifted out of sync.

This guide explains why EPUB TOCs break so easily (the two-file legacy is the culprit), and how to fix every common case — automatically, in an editor, or by hand if you want to understand the machinery.

Why EPUB Has Two Table-of-Contents Files

EPUB's history left it with two navigation systems, and most books carry both:

nav.xhtml — the EPUB 3 standard: an HTML page with a navigation list, human-readable and machine-readable
toc.ncx — the EPUB 2 legacy: an XML playorder map kept for backward compatibility, still what some older readers actually read

A third thing often gets confused with the TOC: the spine in the package file, which defines reading order but displays nothing. When people say "the TOC is wrong", the real problem is in the nav, the NCX, or their disagreement with the spine.

That duplication is exactly why TOCs break: editing tools that update one file but not the other, conversions that regenerate one badly, or chapter renames that leave both files pointing at old filenames.

Symptom → Cause → Fix

Symptom	Cause	Fastest fix
TOC empty or missing	nav/NCX absent or unmanifested	Rebuild (Method 1)
Wrong chapter titles ("Chapter 1" ×20)	TOC generated from defaults, not real headings	Rebuild from headings (Method 1)
Taps jump to wrong location	TOC points at renamed/old files	Rebuild (Method 1)
TOC fine in one reader, broken in another	nav fine but NCX stale (or vice versa)	Rebuild — writes both
TOC shows entries that don't exist	Chapters deleted after TOC generation	Rebuild (Method 1)
Reading order wrong even without TOC	Spine order, not TOC	Editor (Method 2)

Method 1: Rebuild the TOC Automatically (Fastest)

A TOC rebuilder does the whole job from the book's real content: it reads every chapter, extracts the heading structure (h1/h2 levels), and writes a clean nav plus a matching NCX — consistent with each other and with the spine.

With the free EPUB TOC fixer:

Drop in the .epub file.
The tool scans chapters and regenerates the navigation — correct titles, correct targets, correct nesting.
Download and check: the TOC on your reader now mirrors the actual book.

This resolves nearly every TOC problem, because "regenerate from reality" beats "patch the drift" every time. It runs in your browser, so private manuscripts stay private.

Method 2: Fix Order and TOC Together in an Editor

When the TOC problem is really a structure problem — chapters in the wrong reading order, a chapter split into pieces that should be one, sections that deserve TOC entries of their own — rebuild the layout in the online EPUB editor:

Open the book; drag chapters into the right order in the sidebar.
Merge or split chapter files where the structure is wrong.
Fix heading levels inside chapters — the TOC is generated from h1/h2/h3, so a chapter of h2-only text produces a flat or empty TOC.
Export: the TOC and spine are written consistently with the new structure.

The heading-level point is underrated: if a book's TOC looks "flat" — every entry at the same level — the chapters were built with same-level headings. Fixing headings inside the text fixes the TOC hierarchy for good.

Method 3: Hand-Edit the nav File (For the Curious)

Understanding the nav file demystifies the whole system. A minimal nav.xhtml looks like this:

<nav epub:type="toc" id="toc">
  <ol>
    <li><a href="text/chapter1.xhtml">Chapter 1: The Letter</a></li>
    <li><a href="text/chapter2.xhtml">Chapter 2: The Road</a>
      <ol>
        <li><a href="text/chapter2.xhtml#section-2">The Crossroads</a></li>
      </ol>
    </li>
  </ol>
</nav>

The nesting of ol/li elements is the TOC hierarchy; each href must point at a real file path from the book's root. The NCX does the same job in XML with navPoint elements and playorder numbers.

Hand-editing is educational and fine for one or two entries. For anything more, regeneration wins: one typo in a href (wrong case, %20 vs space, missing folder) produces a dead TOC entry — the exact class of error automatic rebuilds cannot make.

Reader Compatibility Notes

Kindle (Send-to-Kindle / conversion): historically reads the NCX; current conversion handles both, but a stale NCX still causes phantom entries — keep both files fresh
Kobo: reads the nav; sensitive to wrong href encodings
BOOX / Onyx: uses the Android reader stack — honors nav nesting, ignores broken entries silently
Apple Books: strict about the nav's epub:type="toc" attribute; books missing it show no TOC at all
Older EPUB 2-only apps: read the NCX only — a book with nav but no NCX shows no TOC

The universal answer is boring and effective: both files, generated together, pointing at real files. That is what Method 1 produces.

Preventing TOC Breakage

Regenerate after structural edits — any tool workflow that renames, splits, or reorders chapters should end with a TOC rebuild
Use real headings in chapter text (one h1 per chapter, h2 for sections) so generated TOCs come out meaningful
Validate after converting — a quick pass with the EPUB checker flags dangling TOC references before your reader finds them
Fix the source, not the symptom — patching the nav while chapters stay misnamed means the next edit breaks it again

Frequently Asked Questions

Why is my EPUB table of contents empty? The nav or NCX file is missing, empty, or not listed in the book's manifest — usually the fault of the tool that produced the book. Rebuilding the TOC from the chapters restores it in one pass.

Can I add a table of contents to an EPUB that never had one? Yes. A TOC rebuilder generates one from the chapter headings — no original TOC required.

Why does the TOC work on my phone but not on my e-reader? Different readers read different files (nav vs NCX) and enforce different strictness. One is valid, the other stale or malformed — rebuilding writes both consistently.

Does the TOC affect reading order? Only indirectly. Reading order is set by the spine in the package file; the TOC is navigation on top of it. If chapters play in the wrong sequence, that's a spine fix — easiest inside a full EPUB editor.

Rebuild It Now

The one-minute fix for a broken table of contents: open the EPUB TOC fixer, drop in the book, download the rebuilt file. Deeper structural problems — wrong order, missing headings — belong in the EPUB editor, where the TOC is rebuilt from a structure you've actually fixed.