EPUB to AZW3

EPUB to AZW3 converter: keep the styling on a Kindle

To convert EPUB to AZW3, drop the EPUB in the box and download the .azw3 file, then copy it to your Kindle's documents folder over USB. AZW3 keeps fonts, headings and layout better than the old MOBI format.

Convert an EPUB to AZW3

  • No sign-up
  • Deleted within an hour
  • Opens in any reading app

Free: 10 files a day. Only convert books you have the right to convert. DRM-protected books, such as most store-bought Kindle books, can't be converted.

nocover.azw3 epubwise
The plain cover epubwise made from the book's title and author
A short test book with no cover, and Pride and Prejudice, read back from each AZW3. On a normal book the two are level, and the table below says so. The difference is the book that arrives with no cover. This shows what the files hold: it is not a photograph of a Kindle.

Why AZW3 rather than MOBI

AZW3, also called KF8, is the Kindle format that replaced MOBI. It understands much of the same styling an EPUB uses: embedded fonts, image placement and nested chapters. When you copy books to a Kindle by cable, an AZW3 usually looks closer to the original EPUB than a MOBI made from the same file.

Self-publishers also use it to check how a book will look on a Kindle before uploading, and readers who keep a library on their computer use it for books they sideload. If you would rather let Amazon do the work, Send to Kindle accepts the EPUB itself: see how to send an EPUB to a Kindle.

What the AZW3 keeps

  1. Contents

    The chapter list, so Go To and the contents menu work on the Kindle.

  2. Styling

    Headings, italics, embedded fonts and pictures from the EPUB.

  3. Book details

    Title, author and cover, so it sorts properly in the Kindle library.

How it compares

Honestly, on an ordinary book, there's nothing between the converters we tried. Tested 4 and 5 November 2026, epubwise's AZW3 matched Calibre's defaults on Alice's Adventures in Wonderland, Frankenstein and Pride and Prejudice, FreeConvert's on Alice and Pride and Prejudice, and online-convert.com's on Pride and Prejudice: the same size of file, with the same text, contents and pictures. Calibre writes AZW3 well, and they all use it.

The one measured difference is a book with no cover. Calibre's defaults, FreeConvert and online-convert.com left it blank, and epubwise makes a plain cover from the title and author. Going the other way? Our MOBI to EPUB and AZW3 to EPUB tables show bigger gaps.

Limits

Only DRM-free EPUBs can be converted. For a device or app that needs the older format, use EPUB to MOBI. The conversion is done by Calibre, the free ebook program, on our server, and the file is deleted within an hour.

Questions

Can I email an AZW3 to my Kindle?

Copy it over USB instead. For email or the Send to Kindle app, send the EPUB itself, which Amazon accepts and converts.

Is AZW3 the same as KF8?

Yes. KF8 (Kindle Format 8) is the format, and .azw3 is the file extension it uses.

What if my EPUB has no cover?

epubwise makes a plain cover from the book's title and author, so it isn't a blank tile in your Kindle library. A book that already has a cover keeps it.

Kindle is a trademark of Amazon.com, Inc. epubwise is not affiliated with Amazon.