MorphjetJoin the waitlist

Ebooks conversion

Convert EPUB to AZW3

Updated Jul 2026

Short answer

EPUB is the format most e-readers and apps use, while AZW3 (Kindle Format 8) is the format Kindle devices and apps expect. To convert, open the EPUB in a converter and export it as AZW3. Doing this on your own computer keeps the book's file, and whatever's inside it, off other people's servers.

Extension
.epub
Type
Ebooks
Typically
Most e-readers
Extension
.azw3
Type
Ebooks
Typically
Kindle

Convert EPUB to AZW3 on your own computer. Nothing uploads.

Launching this July. Everyone on the list gets 30% off on launch day, no spam, just one email when it's ready.

How to convert EPUB to AZW3

  1. Open Morphjet and drag in the EPUB file, or a whole folder of them, that you want to convert.
  2. Choose AZW3 as the output format.
  3. Convert. The AZW3 file is written next to your original, and nothing leaves your machine.

EPUB vs AZW3: what actually changes

EPUBAZW3
Reads on Kindle devices and appsNo, needs conversion firstYes, native format
Reads on other e-readers (Kobo, Apple Books, etc.)Yes, broadly supportedNo, built for Kindle
File sizeCompact, text-based containerSimilar, still compact
QualityLosslessLossless, no recompression of text or images
Metadata (title, author, cover image)YesYes, carries over

When to convert, and when not to

Convert EPUB to AZW3 when you want to read a book on a Kindle device or in the Kindle app, since Kindle doesn't open EPUB files directly.

Keep the EPUB if you're reading on anything other than a Kindle, since EPUB already works there and AZW3 won't open on most other e-readers.

Why not just use an online converter?

Ebooks you've bought or written can carry your name, purchase details, or personal notes right in the file. Uploading an EPUB to a web based converter to get an AZW3 sends that file, and whatever's in it, to a server you don't control. Converting on your own computer means the book never leaves your machine, and there's no upload or download to wait on.

Questions

Does converting EPUB to AZW3 lose quality?

No. Both formats store text and images plainly, so nothing gets recompressed or degraded. Words and pictures come through the same, though very complex layouts can shift slightly since AZW3 handles some formatting differently.

Can I convert an EPUB with DRM to AZW3?

Not with a straightforward converter. If the EPUB is locked by the store you bought it from, most tools, including Morphjet, can't touch it. This works well for DRM-free books, your own writing, and files you're free to convert.

Will the AZW3 keep the book's cover and metadata?

Yes. Title, author, and cover image carry over into the AZW3 file.

Can I convert EPUB to AZW3 without uploading it anywhere?

Yes. A desktop app like Morphjet converts the file on your own computer, so the book never travels over the internet.

Why doesn't Kindle just read EPUB directly?

Kindle devices and apps are built around Amazon's own formats. AZW3 is the one modern Kindles use, so an EPUB needs to be converted before it'll open there.

Morphjet converts EPUB, AZW3, and 1,800+ other formats, all on your machine. Launching this July.

Launching this July. Everyone on the list gets 30% off on launch day, no spam, just one email when it's ready.