The AZW and AZW3 extensions are the proprietary EBook formats from Amazon. Although it’s never been officially confirmed, AZW and AZW3 format are similar to the MOBI format also known as Mobipocket, Developed by a French company in the year 2000 and later acquired by Amazon in 2005.
- AZW is the first version, and was released in 2007 along with the first Kindle,
- Whereas AZW3 also called KF8 was introduced along with the Kindle Fire reader in 2011, AZW3 has more advanced features than AZW. It supports more styles, fonts, layouts and also supports HTML5 and CS3.
- KFX is the latest format on the list. Whereas KFX is an enhancement to the previous formats with added features like layout presentation, using new typesetting engines, supports soft hyphens, it comes with a new image file format called JXR which provides a higher compression ratio, It introduces new Bookerly font which is Amazon exclusive to improve readability on devices.
Android, IOS-based devices, and popular EBook management apps like Calibre and Alfa can read AZW and AZW3 format. The software’s like Calibre, Amazon’s KindleGen, and the email-based Send-to-Kindle service are available free help and convert EBooks into supporting Kindle formats. Generic document formats such as plain text (TXT) and Portable Document Format (PDF) files can also be displayed on Kindle devices, however, reflowing is not supported.
KDP supports a large variety of eBook format. You will find below the information related to the formats we recommend, the tools you can use, and the device compatibility.
While preparing, Think about whether you want your content to be in a fixed or a reflowable format.
- Microsoft Word (DOC/DOCX) – DOC / DOCX files convert well into EBooks. However, some complex eBook format files may not be converted as well. You can always check your converted EBook using Kindle Previewer, Compatible with Fire Tablets and Kindle App
- Package Format (KPF) – KPF allows your EBook to be easily formatted and fit for all Kindle devices, Create a KPF file by using Kindle Create. Compatible with Fire Tablets and Kindle App, Benefits of using Kindle Create, take care of typesetting, wide range of themes and style to customize EBook, Easy to create a table of content, Image integration and preview option before publishing.
- EPUB – Support EBook in EPUB format which meets the specification of Kindle Publishing guideline, Strongly recommend Kindle Previewer to validate before upload. Compatible with Fire Tablets and Kindle App
Supported eBook Formats
- HTML (ZIP, HTM, or HTML) – Save the HTML file as a Web Page, This will create a folder with HTML manuscript, and image files, compress to a Zip file, and upload it to KDP, Compatible with Kindle App
- MOBI – Support fixed-layout EBooks that meet the specification of Kindle Publishing guidelines, For reflowable EBooks used EPUB, DOCX, or KPF file format. Compatible with Fire Tablets, Kindle App, and E-Ink
- Rich Text Format (RTF) – RTF is a highly acceptable and readable eBook format across programs and platforms, and it is simple to use. Compatible with Kindle App
- Plain Text (TXT) – TXT manuscript files are limited to plain text, it does not contain any images, KDF can convert a plain text to HTML, Compatible with Fire Tablets, Kindle App and E-Ink
- Adobe PDF (PDF) – PDF files are accepted but they can contain embedded formatting and images that do not convert well. Compatible with Fire Tablets, Kindle App, and E-Ink, KDP only supports PDFs with the following languages: English, French, German, Italian, Portuguese, Spanish, Catalan, Galician, and Basque.