AZW1 file format is used as Amazon Topaz eBook file format. This file format is similar to Topaz file format for eBook.

This file format is used to display eBooks on Amazon Kindle. This file format can also be used to display contents of the eBook on mobile devices which can use Whispernet service of Amazon. The file format is based on XML based structure. Each page of the document is treated as a separate document. All the character glyphs added in the document are created with scalable vector graphics. The output of this file is in the form of automatic converted images.