.APNX File

The apnx file extension is mainly associated with Amazon Kindle ebook platform and used for one of its default file type.

This type of apnx files was introduced to Kindle in firmware revision 3.1 and represents an index, generated to map and speedup the loading of pages of individual e-books.

Files with apnx suffix can be typically found as ebook index files from Amazon Kindle platform. Used to speedup loading of ebooks.

How to open:

When you open a book in Kindle, its index is loaded automatically to improve the loading times.

How to convert:

Index files usually cannot be converted to anything else, they are generated to speedup loading of the Kindle ebook.