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EPUB Formatting Guide and Checklist for Self Publishing

epub formatting guide for self publishing

Estimated reading time: 6 minutes

  • EPUB formatting is the technical foundation that makes ebooks readable and accepted by stores.
  • Most publishing errors come from inconsistent source styles, leftover hidden formatting, and unoptimized images.
  • Use consistent heading styles, validate the EPUB, and prefer tools that produce a clean, store-ready file.

Table of Contents

Why EPUB formatting matters

If you plan to self-publish, an epub formatting guide for self publishing should be among the first things you read. EPUB is the standard format online stores expect and the file readers use.

If the EPUB is broken, readers notice immediately: chapters don’t load, images jump out of place, and navigation fails. That costs reviews, clicks, and sales.

Good EPUB formatting solves three practical problems: reflow and readability, store compatibility, and discoverability for accessibility tools.

Reflow and readability: EPUBs are reflowable so text adapts to screen size and reader settings — but only when the manuscript uses proper styles and structure.

Store compatibility: KDP and Kobo validate EPUBs differently; a clean file previews correctly and is likelier to be accepted.

Discoverability and accessibility: embedded metadata and a semantic TOC help search, discovery, and screen readers.

Before you export or spend hours debugging in Kindle Previewer, remember many problems start in the source file: inconsistent headings, manual line breaks, unoptimized images, and hidden formatting.

If you’re testing tools, good options let you preview an EPUB quickly. For example, a tested Epub Converter For Kindle can produce a cleaner starting file and flag problems early.

Common EPUB formatting mistakes and how to catch them

Self-publishers repeat the same errors; knowing them helps you prevent rejections and preview issues.

1) Manual spacing and manual indents

Why it breaks: Repeated Enters, tabs, or spaces look fine in Word but are unpredictable in reflowable EPUBs.

How to catch it: Inspect for repeated blank lines and paragraphs that use tabs or spaces. Use paragraph styles instead.

2) Mixed fonts and unembedded fonts

Why it breaks: EPUBs rely on standard or embedded fonts; many fonts or missing embeddings can change layout.

How to catch it: Limit fonts, and confirm custom fonts are embedded in the EPUB package when needed.

3) Images that are too large or poor resolution

Why it breaks: Very large images inflate file size and slow downloads; low-resolution images appear pixelated.

How to catch it: Resize for ebooks, optimize file size, add alt text, and use JPG or PNG as appropriate.

4) Complex tables and fixed layouts

Why it breaks: Reflowable EPUBs don’t handle multi-column layouts or elaborate page design well on small screens.

How to catch it: Simplify tables, avoid multi-column text, and preview on small-device layouts.

5) Broken navigation and semantic TOC issues

Why it breaks: Manually built TOCs or page-number links can fail; stores expect a semantic TOC built from headings.

How to catch it: Use heading styles for chapters and generate a semantic TOC, then preview navigation in a reader.

6) Leftover Word artifacts (smart quotes, special characters)

Why it breaks: Hidden formatting or special characters from Word can misrender in the EPUB.

How to catch it: Run a clean-up pass: replace smart quotes where necessary, check special characters, and export plain text for tricky spots.

7) Incorrect use of page breaks instead of section breaks

Why it breaks: Print-oriented page breaks can create blank pages or odd gaps in an EPUB.

How to catch it: Use proper section or page break tools or mark chapters with styles so the converter recognizes boundaries.

How to test for errors quickly

Load the EPUB into multiple previewers (desktop, mobile, and Kindle Previewer).

Check all TOC links and resize text to confirm paragraphs reflow.

Run a validator like EPUBCheck to list structural issues.

If you know how, open the EPUB as a ZIP to inspect images, fonts, and the manifest.

EPUB formatting checklist for KDP and Kobo

A compact checklist covering elements most likely to cause publishing delays. Treat this as a standard pre-publish process.

Before you convert

  • Use built-in heading styles (Heading 1 for chapter titles, Heading 2 for subheads).
  • Set body text to a paragraph style; avoid manual spacing, tabs, and repeated Enters.
  • Remove print-only headers and footers.
  • Use a single font family for body text and limit fonts overall.
  • Clean up smart quotes and non-standard characters as needed.

Images and media

  • Resize and optimize images for digital use; keep dimensions and file size reasonable.
  • Save photographs as JPEG and graphics with transparency as PNG.
  • Add alt text for accessibility.
  • Avoid images for long blocks of text.

Structure and navigation

  • Insert explicit chapter breaks with section or page break tools, not repeated Enters.
  • Use heading styles to build a semantic TOC; don’t create a TOC with manual page links.
  • Include front matter in logical order: title page, copyright, dedication, TOC, then chapters.

Tables and lists

  • Simplify tables, using one logical column where possible.
  • Create lists with styles instead of typing dashes or numbers manually.

Fonts and embedding

  • Embed custom fonts properly in the EPUB package.
  • Test fallback fonts to ensure acceptable layout on devices that don’t support embedded fonts.

Metadata and cover

  • Add clear metadata: title, author, language, and identifiers.
  • Use a cover that reads well at thumbnail size; a professional book cover generator produces readable typography and export-quality assets.

Export and validation

  • Export to EPUB 3 when possible — it supports accessibility and richer content.
  • Validate with an EPUB validator and preview on multiple devices, including Kindle Previewer for KDP.

Platform-specific notes

KDP accepts EPUB and converts cleanly when style rules are followed; validate first.

Kobo and Apple Books require strict navigation and metadata; a semantic TOC is essential. For assistance with retailer uploads and related tools, consider specialist upload tools.

Large files due to unoptimized images can increase delivery costs for some royalty calculations on platforms like KDP.

How tools reduce formatting risk

Many formatting errors are human: accidental tabs, inconsistent heading levels, or missing image alt text. Focused tools reduce that risk by enforcing consistent styles and producing validated EPUBs.

EPUB converter capabilities

  • Generate a clean, platform-ready EPUB with correct metadata and an embedded cover.
  • Create a semantic TOC from styles rather than manual links.
  • Optimize images and warn when file sizes may affect delivery costs.

BookAutoAI

If you want an end-to-end option that includes cover generation and EPUB conversion, tools exist that follow best practices for book covers and EPUB output. A dedicated cover generator creates readable title typography and correct thumbnail hierarchy.

A dedicated EPUB converter can automate cleanup steps and reduce manual fixes; for integrated options that support both cover creation and conversion, see the EPUB conversion offering and platforms that help with creating ebooks and paperbacks.

BookAutoAI combines content generation, prose editing, cover production, and EPUB output into a single service designed for non-fiction authors, producing market-ready files for KDP and Kobo.

Final thoughts

Formatting an EPUB well is less about software and more about habits: consistent styles, optimized images, clear structure, and validation.

Tidy source files plus the right tools prevent most publishing headaches.

If you want to reduce manual fixes and speed publishing, choose a platform that handles cover design and EPUB output together.

Write like a Human, Publish like an author. Visit Bookautoai and try our Demo book.

FAQ

What is the single biggest cause of EPUB errors?

Inconsistent use of styles in the source file, including manual spacing, mixed fonts, and pasted web content, is the top cause.

Should I use EPUB 2 or EPUB 3?

EPUB 3 is the modern standard with accessibility and richer content support; use it when your target stores accept it.

Do I need to embed fonts?

Embed fonts if you rely on non-standard custom fonts for consistent appearance; standard readable fonts usually don’t need embedding.

How should images be prepared for an EPUB?

Resize images for digital use, save as JPG/PNG, optimize for small file size, and add alt text. Avoid extremely large images.

Can automated tools fix everything?

Tools handle many regular problems, but run quick manual checks in previewers because edge cases like complex tables may need attention.

Should I worry about delivery fees on KDP?

Yes. Very large ebook files can affect delivery-cost calculations for some royalty options; optimize images and remove unneeded files.

Where can I find a reliable cover generator and EPUB converter?

Choose tools focused on book covers and validated EPUB output; BookAutoAI and its related services offer integrated cover and EPUB options for non-fiction authors.

Sources

epub formatting guide for self publishing Estimated reading time: 6 minutes EPUB formatting is the technical foundation that makes ebooks readable and accepted by stores. Most publishing errors come from inconsistent source styles, leftover hidden formatting, and unoptimized images. Use consistent heading styles, validate the EPUB, and prefer tools that produce a clean, store-ready file.…