Free online AZW to MOBI converter

Source format: AZW

AZW is an Amazon Kindle ebook format used in the Kindle ecosystem. It is closely related to older Kindle and Mobipocket formats and may include DRM protection, Amazon-specific metadata, and Kindle formatting. AZW files are commonly used for ebooks intended for Kindle devices and the Kindle app.

Because AZW is tied to Amazon’s platform, it is mainly useful for personal Kindle libraries, syncing reading progress across Kindle devices and apps, and reading books purchased or downloaded through Amazon services.

Target format: MOBI

MOBI is an older ebook format that originated with Mobipocket and was later supported by Amazon Kindle devices. It supports reflowable text, bookmarks, and basic formatting, and it has long been recognized by many ebook readers and conversion tools.

The main reason to convert to MOBI is compatibility with older Kindle devices and legacy ebook software. However, MOBI is now considered a legacy format, and Amazon has largely moved away from it for newer Kindle workflows.

How to perform the conversion

The most practical desktop tool for converting AZW to MOBI is Calibre. It is free, works on Windows, macOS, and Linux, and is designed for ebook management and format conversion.

1. Install and open Calibre.
2. Add the AZW file to your library by clicking Add books or dragging the file into the window.
3. Select the imported book.
4. Click Convert books.
5. In the conversion window, choose MOBI as the output format.
6. Review options such as metadata, page setup, heuristic processing, and look and feel if you want to adjust formatting.
7. Click OK to start the conversion.
8. When finished, right-click the book and choose Save to disk, or open the output folder from Calibre’s library location.

If you prefer a command-line workflow, Calibre’s ebook-convert tool can also perform the conversion. Example: ebook-convert input.azw output.mobi

You can also convert the file on 101convert.com for free, without installing any software.

Important limitations

DRM-protected AZW files cannot be converted normally unless the DRM is removed with authorized tools and in compliance with applicable laws. If the file is protected, conversion may fail or produce an unreadable result.

Formatting quality depends on the source ebook. Simple text-based AZW files usually convert well, while books with complex layouts, embedded fonts, tables, or images may need manual cleanup after conversion. Some Kindle-specific features may not carry over perfectly to MOBI.

Also note that MOBI is an older format. For many modern Kindle workflows, AZW3 or EPUB may be better long-term choices, but MOBI remains useful for older devices and software that still expect it.

If your goal is simply to read the book on a Kindle device, you may not need to convert at all, since many Kindle devices can already open AZW files directly.