Free EPUB Converter for Amazon KDP & IngramSpark Pro

Free DOCX to EPUB Converter — What This Tool Does

This tool converts your Word document (.DOCX) into a valid EPUB 3.3 file for Amazon Kindle, Apple Books, IngramSpark, Kobo, and Barnes & Noble Press — all from a single upload. If you are publishing a picture book or illustrated title, it also converts PDF to fixed-layout EPUB, preserving every illustration exactly as you placed it.

No software to install. No account required. Files up to 1GB are supported.

Reflowable EPUB vs Fixed-Layout EPUB — Which Do You Need?

The most important choice when creating an EPUB is whether your content needs to be reflowable or fixed-layout. The table below explains the difference and which book types use each format.

	Reflowable EPUB	Fixed-Layout EPUB
Best for	Novels, short stories, biographies, poetry	Picture books, comics, graphic novels, photography books
Input file	.DOCX (Microsoft Word)	.PDF
Layout	Adapts to screen size and reader font preferences	Frozen — every element stays exactly where placed
Kindle/KDP	✅ Supported	✅ Supported (Kindle Fire, iPad)
Apple Books	✅ Supported	✅ Supported
Night Mode	✅ Reader-controlled	Not available (layout is fixed)

What Makes This EPUB Converter Different

1GB File Support

Most free EPUB converters limit files to 50–100MB, which is too small for illustrated children's books, graphic novels, or any title with full-resolution artwork. This tool uploads your file in 5MB chunks, so even a 1GB PDF converts without browser timeouts or server crashes.

EPUB 3.3 Compliance and Accessibility

The output meets the current EPUB 3.3 standard — the version required by Amazon KDP, Apple Books, and IngramSpark as of 2024. Every generated file includes:

• NCX and NAV Table of Contents — for compatibility with both older and newer e-readers
• ARIA roles and alt text on images — required by Apple Books for accessibility compliance and recommended by KDP
• Correct OPF metadata — ISBN, publisher, language, and publication date in the right format
• Validated file structure — reduces the risk of KDP rejection on upload

Auto Chapter Detection for Novels

When converting a DOCX file, the tool scans for paragraphs styled as Heading 1 in Microsoft Word and automatically turns each one into a chapter — complete with its own entry in the Table of Contents. No manual markup required.

How to Prepare Your Files for Best Results

For Novels and Text Books (.DOCX)

• Apply Heading 1 style to every chapter title in Microsoft Word — this is how chapters are detected and the Table of Contents is built.
• Use *** or --- on its own line to create a scene break (the converter renders these as a decorative separator).
• Avoid manual page breaks for chapter starts — Heading 1 handles this automatically.
• Keep images inline with text; do not use text boxes or floating image frames.
• Remove any custom fonts embedded in the DOCX — EPUB readers use their own font system.

For Picture Books and Illustrated Titles (.PDF)

• Make sure all pages are the same size throughout the PDF — the converter uses page 1 dimensions for the entire EPUB.
• Export your PDF at 300 DPI minimum for print-quality illustrations on high-resolution tablets.
• Flatten all layers and transparency before exporting from InDesign or Affinity Publisher.
• Avoid password-protected PDFs — they cannot be processed.

Frequently Asked Questions

Is the output compatible with Amazon KDP?

Yes. The generated EPUB 3.3 files pass Amazon KDP's automated quality checker. The tool includes all required metadata, accessibility markup, and a valid Table of Contents in the formats KDP expects.

What is the maximum file size?

Up to 1GB. Large files are uploaded in 5MB chunks to avoid timeouts — making this one of the few free converters that handles full-resolution graphic novels and heavily illustrated children's books.

Does it work for Apple Books and IngramSpark?

Yes. The EPUB 3.3 output is compatible with Apple Books, IngramSpark, Barnes & Noble Press, Kobo, and Google Play Books, in addition to Amazon KDP.

Can I use this for a children's picture book?

Yes — select Picture Book mode and upload your PDF. Each page of the PDF is converted into a high-resolution image and placed in a fixed-layout EPUB, preserving illustrations exactly as designed. This format works on Kindle Fire, iPad, and most color e-readers.

How do I validate my EPUB after downloading?

You can validate the output using the free EPUBCheck tool (epubcheck.org) or the Ace by DAISY accessibility checker. Both are free and check your EPUB against the EPUB 3.3 specification and WCAG accessibility guidelines. Amazon KDP also runs its own validation when you upload the file.

Are my files kept private?

Yes. All uploaded files are stored privately and deleted automatically within 2 hours. No files are shared with third parties.

What chapter heading style should I use in Word?

Apply the built-in Heading 1 paragraph style to every chapter title. In Microsoft Word, select the text, then click Heading 1 in the Home tab Styles panel. Do not use bold text alone or manually increased font sizes — the converter looks for the actual Heading 1 style tag.

Does this tool support languages other than English?

Yes. You can set the EPUB language to English, Hindi, French, Spanish, or German in the Language dropdown. This sets the correct xml:lang attribute in the EPUB file, which affects how screen readers and e-readers handle hyphenation and text direction.

Related tools from Kidillus:
Free ISBN Barcode Generator  ·  KDP Cover Template Calculator  ·  KDP Description HTML Formatter  ·  Picture Book Paginator

Disclaimer: This tool generates EPUB files based on the structure and content you provide. The quality of the output depends on the formatting of your source DOCX or PDF. Kidillus recommends validating the final EPUB with EPUBCheck before submitting to any distributor.