If you've ever tried moving an ebook from Apple Books to a Kindle, you've probably run into problems. The book won't open, the formatting is broken, or Amazon just rejects the file entirely.
The issue isn't your Kindle. It's what Apple Books does to EPUB files behind the scenes.
Why Apple Books breaks EPUB files
When you add an EPUB to Apple Books (formerly iBooks), it unpacks the file and stores it as a directory of loose files. This is fine as long as you only read in Apple Books. But the moment you try to export or share that book, the resulting file is no longer a valid EPUB.
A proper EPUB is a ZIP archive with specific structure:
- The
mimetypefile must be the first entry in the ZIP - It must be stored uncompressed (no deflation)
- The rest of the files follow in compressed form
Apple Books doesn't respect these rules when repackaging. The result is a ZIP file that looks like an EPUB but fails validation on every other reading app. For a deeper technical breakdown, see Why Your Apple Books EPUB Doesn't Work on Kindle.
What happens when you try to send it to Kindle
Amazon's Send to Kindle service and Calibre both validate EPUB structure before converting. When they encounter an Apple Books export, you'll see errors like:
- "This file is not a valid EPUB"
- "Failed to convert: invalid container"
- The book uploads but pages are blank or missing
If you're hitting import errors in Calibre specifically, see our guide to fixing EPUB files that Calibre can't import.
How to fix it
You have two options:
Option 1: Use our free EPUB Fixer tool
The fastest way. Upload your broken EPUB file and get a properly formatted one back:
- Go to EPUB Fixer
- Drag and drop your EPUB file
- Download the fixed version
- Send it to your Kindle via email or USB
The tool repackages the ZIP with the correct structure — uncompressed mimetype first, everything else compressed. No data is stored on our servers.
Option 2: Fix it manually with a terminal
If you prefer the command line:
# Unzip the broken EPUB
mkdir temp && cd temp
unzip ../broken-book.epub
# Repackage correctly
zip -X0 ../fixed-book.epub mimetype
zip -rX9 ../fixed-book.epub . -x mimetype
cd .. && rm -rf temp
The key flags: -X0 stores mimetype without compression, -rX9 compresses everything else.
Sending to Kindle after fixing
Once you have a valid EPUB, the easiest way is PaperDrop — a Telegram bot that delivers files straight to your Kindle. Just send it the EPUB and it handles the rest. It can even fix broken Apple Books EPUBs automatically, so you can skip the manual step entirely.
Or do it manually:
- Email: Send the EPUB to your Kindle email address (find it in Amazon settings under "Send-to-Kindle Email")
- USB: Connect your Kindle and copy the file to the
documentsfolder - Send to Kindle app: Use Amazon's desktop app to transfer files wirelessly
Preventing the problem
To avoid this issue entirely:
- Don't import EPUBs into Apple Books if you plan to use them elsewhere. Keep the original files in a folder.
- Use Calibre as your ebook library manager — it preserves proper EPUB structure. If you run into issues importing, here's how to fix EPUBs that Calibre rejects.
- Back up originals before importing into any reading app.
If you've already imported books into Apple Books and lost the originals, the EPUB Fixer tool is your best bet for recovering them in a usable format.