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How to Make an EPUB File That Passes EPUBCheck for KDP

How to Make an EPUB File: Build a Store-Ready EPUB That Passes Validation

Estimated reading time: 5 minutes

  • A clean source document with consistent styles and clear headings is the fastest path to a valid EPUB.
  • Choose the conversion path that matches your needs: quick exports for simple books, converters for balance, and editors for full control.
  • Validate with EPUBCheck and test on multiple readers early to avoid store rejections.

Table of Contents

Prepare your manuscript

A good EPUB begins long before you hit “export.” If you want an EPUB that reliably passes store checks, start with a clean source and consistent structure.

If your end goal is Kindle, there’s a helpful route that targets Kindle validation and previewing — see our Epub Converter For Kindle for a practical walk-through and tips that save time when you plan to publish on Amazon KDP.

Why the source matters

EPUBs are reflowable files built from HTML and CSS under the hood. Formatting quirks in Word or Google Docs become structural issues in the EPUB.

The cleaner and more consistent the source, the fewer surprises after conversion.

Practical rules for your manuscript

  • Use real styles: Heading 1 for chapter titles, Heading 2 for sections, and Normal for body text.
  • Avoid manual page breaks and tab-based layout; let the EPUB handle pagination.
  • Keep images inline and start from clear source files; complex floats often reflow unpredictably.
  • Avoid multi-column layouts or heavy tables unless you plan to handle EPUB editing manually.
  • Use UTF-8 and standard quotes, dashes, and apostrophes to avoid odd characters.

Convert: tools and best paths

Once your manuscript is tidy, pick the conversion path that matches your need for speed or control. A reliable EPUB converter can simplify metadata and image handling.

If you need an integrated option to turn a finished manuscript into a store-ready file, consider an EPUB converter that preserves structure and metadata; a purpose-built EPUB converter can be the fastest path to a validated file for multi-store uploads.

Three common routes

1. Export from your writing tool (fast, low control)

  • Microsoft Word: save as .docx and export or use a converter; Word’s EPUB export works for simple books but may add extra styling.
  • Google Docs: export to .docx first, then convert.
  • Use this when the book is mostly text with simple images and clear styles.

2. Use a free converter or EPUB maker (balanced speed)

  • Tools such as Calibre or web-based converters import .docx and export EPUB while handling metadata and images more consistently than raw Word export.
  • For many authors, these converters are sufficient for text-heavy non-fiction.

3. Use a dedicated EPUB editor (maximum control)

  • Editors like Sigil or tools like Pandoc let you edit HTML/CSS directly and are best when you need exact control over navigation, typography, or complex layouts.
  • This route takes time but yields the cleanest, most reliable results for designed books.

Which path for non-fiction?

Most non-fiction authors benefit from a middle path: tidy the manuscript in Word, export to .docx, then use a reliable converter that preserves headings and metadata.

Free EPUB makers often suffice for text-heavy books; a dedicated editor is worth the effort for image-heavy guides or interactive files.

Validate, test, and fix common EPUB errors

After conversion, validation and testing are the most important steps — stores run automated checks that can reject files with structural or metadata issues.

Run EPUBCheck

EPUBCheck is the standard validator for missing files, incorrect metadata, broken navigation, and packaging errors. Make EPUBCheck part of your process early.

Common validation issues and fixes

  • Missing or wrongly embedded cover: embed the front cover correctly and ensure metadata points to it.
  • Broken links and missing images: include all image files in the package and use proper internal anchors or absolute external URLs.
  • Poor TOC structure: fix heading hierarchy in the source and rebuild the TOC.
  • Inline styles from Word: strip redundant inline styles to prevent inconsistent rendering.
  • Incorrect metadata: ensure title, author, language, and identifiers are accurate.

Test on multiple readers

Different readers render EPUBs differently. Test at minimum on Kindle Previewer, Apple Books, and a common Android EPUB reader.

If you plan to upload beyond Kindle, test store previewers to catch platform-specific quirks.

Fixing complex layout problems

When a converter can’t preserve advanced layouts, consider a fixed-layout EPUB only if the design must stay exact.

Otherwise, use a dedicated editor to hand-correct HTML/CSS or simplify the layout to a reflowable model for broader compatibility.

Metadata, cover, and upload-ready packaging

Stores look beyond the book body. A properly packaged EPUB includes clean metadata, a thumbnail-ready cover, and correct navigation.

Metadata checklist

  • Title, subtitle, and author spelled consistently.
  • Language set correctly and identifiers (ISBN optional).
  • Publisher and rights statements where relevant.
  • Proper subject tags or categories where supported.

Covers that sell (and pass checks)

A good cover must read well at thumbnail size and be embedded correctly. If you prefer an automated cover option, try the BookAutoAI Cover Generator for market-ready designs and proper embedding.

Embed the image and mark it as the cover in the EPUB metadata.

Pack everything into a clean EPUB

  • Include front matter (title page, copyright, TOC).
  • Ensure chapters are separate XHTML files and linked in the spine.
  • Avoid large unused files that bloat EPUB size.
  • If you plan both ebook and paperback, keep EPUB focused on reflowable layout and use separate print files for fixed, print-ready designs.

Publishing workflows and stores

Amazon KDP accepts .docx and will convert it, but uploading a validated EPUB reduces the chance of formatting shifts. Many authors upload a validated EPUB or use Kindle Create to limit surprises.

If you prepare for multiple stores, a validated EPUB that follows standards is your best bet; some platforms and services also offer uploader tools for distribution—consider specialized upload support such as book upload tools when you need retailer-specific handling.

For a single platform that walks you from manuscript to validated EPUB and includes automatic cover generation, BookAutoAI bundles manuscript formatting, conversion, and cover production for a simplified multi-format publishing approach.

Final steps

A reliable EPUB workflow is about preparation, choosing the right conversion path, and validating the result. Tidy your manuscript, pick the conversion option that fits your book’s complexity, run EPUBCheck, and test on multiple readers.

When you need end-to-end solutions that include cover generation and validated EPUB output in one place, consider platforms that centralize those outputs and support multi-format publishing.

FAQ

Can I create an EPUB from Word for free?

Yes. Export or save a Word document and use free converters like Calibre or online EPUB makers. The key is consistent styles in Word so the converter builds clean structure.

Are free EPUB makers reliable for KDP?

For straightforward non-fiction and text-heavy books, free EPUB makers are often sufficient. For higher certainty, use a tool that prepares metadata and runs checks before upload.

How do I make an EPUB for KDP specifically?

KDP accepts .docx and will convert it, but uploading a validated EPUB reduces formatting shifts. Run EPUBCheck and preview in Kindle Previewer before uploading.

Is there a free EPUB file maker that preserves images well?

Some free tools handle images well for basic needs, but complex image layouts may not survive automated conversion. For image-heavy books, consider an editor or a conversion service that preserves image placement.

My EPUB failed EPUBCheck—what now?

Read the error messages, correct missing files, fix malformed XML, and ensure images are referenced correctly. If errors are confusing, try a different converter or open the EPUB in an editor like Sigil to inspect the package.

Should I test on multiple readers before upload?

Yes. Test on Kindle Previewer, Apple Books, and a common Android EPUB reader to catch rendering differences and retailer quirks.

Sources

How to Make an EPUB File: Build a Store-Ready EPUB That Passes Validation Estimated reading time: 5 minutes A clean source document with consistent styles and clear headings is the fastest path to a valid EPUB. Choose the conversion path that matches your needs: quick exports for simple books, converters for balance, and editors for…