Ebooks conversion
Convert MOBI to AZW3
Updated Jul 2026
MOBI is the ebook format older Kindles used, and AZW3 (Kindle Format 8) is what current Kindles and the Kindle app expect. To convert, open the MOBI file in a converter and export it as AZW3. Doing this on your own computer means the book itself, and what it says about what you're reading, never has to leave your machine.
- Extension
- .mobi
- Type
- Ebooks
- Typically
- Older Kindles
- Extension
- .azw3
- Type
- Ebooks
- Typically
- Kindle
Convert MOBI to AZW3 on your own computer. Nothing uploads.
How to convert MOBI to AZW3
- Open Morphjet and drag in the MOBI file, or a whole folder of them, at once.
- Choose AZW3 as the output format.
- Convert. The AZW3 file is written next to the original, and nothing leaves your machine.
MOBI vs AZW3: what actually changes
| MOBI | AZW3 | |
|---|---|---|
| Works on current Kindles | No, Amazon no longer accepts MOBI files for sending to Kindle | Yes, it's the native format for modern Kindles |
| Works on older Kindles (2007-2011) | Yes | No, needs a newer Kindle or the Kindle app |
| File size | Similar | Similar, sometimes a little larger |
| Quality | Lossless | Lossless, nothing is recompressed |
| Formatting and layout support | Basic, simple text flow | Richer, supports more complex layouts and embedded fonts |
| Keeps title, author, and cover | Yes | Yes |
When to convert, and when not to
Convert MOBI to AZW3 when you want to read an older ebook on a current Kindle or in the Kindle app, since Amazon has moved away from accepting MOBI files.
Keep the MOBI file if you only read on an old Kindle from 2007 to 2011, since those devices understand MOBI but not AZW3.
Why not just use an online converter?
What's in your ebook library, and what you're choosing to read, isn't something you owe to a stranger's server just to change a file extension. An online converter has to receive the whole MOBI file, book and all, before it can hand back an AZW3. Converting on your own computer keeps the book exactly where it already was, on your machine, the whole time.
Questions
Does converting MOBI to AZW3 lose any quality?
No. Both formats store the same text and images, and converting between them doesn't recompress or drop anything, the words and pictures come through unchanged.
Will the AZW3 keep the book's cover and metadata?
Yes. The title, author, and cover image carry over from the MOBI file to the AZW3 file.
Can I still read the AZW3 file on an old Kindle?
No. Kindles from 2007 to 2011 only understand MOBI. If you're reading on one of those, keep the MOBI file instead of converting it.
Does this work on books bought from Amazon with DRM?
Morphjet converts the file itself. If a book is locked to your account with DRM, that protection needs to be removed first before any converter, including Morphjet, can read the file.
Can I convert MOBI to AZW3 without uploading the file anywhere?
Yes. Morphjet runs the conversion on your own computer, so the ebook never travels over the internet. You can do it with your wifi off.
Morphjet converts MOBI, AZW3, and 1,800+ other formats, all on your machine. Launching this July.