PDF to EPUB for Publishers — Distribution-Ready Conversion Guide
If you're self-publishing or working in a small press, you need an EPUB that passes retailer validators — not just one that opens in a reader. Here's what KDP, IngramSpark, Kobo Writing Life, and Apple Books actually require, and how to convert your PDF manuscript to meet those specs.
What retailers require
| Retailer | EPUB version | Validator |
|---|---|---|
| Amazon KDP | EPUB 3 preferred, EPUB 2 accepted | KDP's internal validator |
| IngramSpark | EPUB 3 | EPUBCheck 4.x |
| Kobo Writing Life | EPUB 3 | EPUBCheck |
| Apple Books | EPUB 3 | Apple Transporter (runs EPUBCheck) |
toolkit.bot produces EPUB 3.x output that passes EPUBCheck — the validator used by IngramSpark, Kobo, and Apple Books. KDP accepts the output directly.
Step 1: Convert the PDF
- Go to toolkit.bot/pdf2epub
- Upload your manuscript PDF (max 50 MB)
- Download the EPUB
The converter produces a valid EPUB 3 with: HTML5 content documents, a NAV navigation document, proper metadata in the OPF package, and EPUB Accessibility 1.1 conformance claims.
Step 2: Validate with EPUBCheck
Before uploading to any retailer, validate locally:
java -jar epubcheck.jar your-book.epubtoolkit.bot output passes EPUBCheck. If you've edited the EPUB after conversion and introduced errors, EPUBCheck will identify them. Download EPUBCheck from the W3C EPUBCheck releases page.
Step 3: Add metadata (title, author, ISBN)
The converter carries over metadata from the PDF if present. For publishing, you'll want to verify and add:
- Title and subtitle
- Author name (as it should appear in the store)
- ISBN (required by IngramSpark, optional for KDP)
- Language code (
en,fr, etc.) - Cover image (the converter doesn't add a cover — retailers need one)
Use Sigil (free, open source) or Calibre's metadata editor to add these before uploading.
Cover image
Retailers require a cover image embedded in the EPUB as a specific item with the cover-image property in the OPF manifest. The converter doesn't add a cover. Add one with Sigil: Tools → Add Cover.
Why not just upload a PDF to KDP?
KDP accepts PDF for print books but strongly prefers EPUB for Kindle ebooks. PDFs converted to Kindle format by Amazon's internal process often lose formatting — especially for reflowable text. Uploading a proper EPUB gives you full control over the reading experience. Full self-publishing guide →
Wide distribution (non-Amazon)
For "going wide" — distributing to Kobo, Apple Books, Barnes & Noble, and other retailers — use a distributor like Draft2Digital or Smashwords (now merged with D2D), or upload directly to each retailer. All accept EPUB 3. EPUB 3 vs EPUB 2: what changed →
Convert your manuscript PDF to distribution-ready EPUB3 — free.
Convert PDF to EPUB →Frequently asked questions
What EPUB format do publishing platforms require?
All major ebook retailers require EPUB 3: Amazon KDP, IngramSpark, Kobo Writing Life, Apple Books, and Barnes & Noble Press. EPUB 2 is no longer accepted for new title submissions on most platforms. Your EPUB must also pass EPUBCheck validation (the industry standard checker, free from the DAISY Consortium) before submission.
Can I convert my PDF manuscript to EPUB for KDP publishing?
toolkit.bot converts PDF to EPUB 3, which KDP accepts. Quality depends on your source PDF — if it was typeset from Word or a writing tool with clear heading structure, the conversion typically produces a usable EPUB. Complex fixed designs, intricate layouts, or illustrated books may need manual EPUB authoring. For text manuscripts, toolkit.bot is a fast starting point.
Does EPUB output from toolkit.bot pass EPUBCheck?
toolkit.bot produces structurally valid EPUB 3 that passes EPUBCheck for most documents. Very complex PDFs with unusual formatting may produce EPUBs needing minor fixes — missing alt text, table structure issues. Always run EPUBCheck (free at daisy.org/epub/checker) on your output before submitting to any retailer.
What do ebook retailers check when you submit an EPUB?
Retailers run automated EPUB validation on submission. All check: EPUB 3 format, valid OPF package, required metadata (title, language, identifier), EPUBCheck with no critical errors, and a cover image. Apple Books is the strictest and also checks CSS compliance and encoding. IngramSpark additionally requires EPUB Accessibility 1.1 compliance for new submissions from 2026.