Amazon KDP
KDP EPUB submission hub
Prepare, check, and fix EPUB files before you upload to Kindle Direct Publishing.
Verify EPUB for KDPOverview
KDP rejects many EPUBs for package, metadata, navigation, and HTML/CSS issues. Cermify maps those failures to machine rules and, where safe, automatic repair.
Submission checklist
- Cover meets KDP size and quality rules
- Required OPF metadata (title, language, identifier)
- Manifest includes every package file
- Spine / reading order is complete
- TOC / NCX / nav links resolve
- Content is UTF-8 and well-formed
- Run machine verification before upload
Common errors
- Invalid HTML/CSS construct (RSC-005 family)
- Missing or mismatched NCX / nav document
- Table of contents points to missing content
- Missing required metadata (title, language, identifier)
- Reading order (spine) is empty or broken
- Incorrect or missing mimetype / manifest entries
- Non-UTF-8 encoded content file
- Severe HTML nesting errors