Amazon Kindle Fire only supports azw/prc/mobi/tpz. thus epub and pdf can not be natively accepted by Kindle Fire.
So how to import the epub and pdf to Kindle Fire?You need a third-party software program. There is a variety of software programs designed for solving the problem. The epubsoft adobe epub and pdf drm removal is highly recommended. With it, you can convert epub and pdf to Kindle Fire freely.
With this epubsoft adobe epub and pdf drm removal, you just need to click a few buttons to copy the books and then convert them. Following are some instructions to how to convert the epub and pdf books format to Kindle Fire friendly format.
the simplest way to import epub to kindle fire
just refer to it, see, it is so easy!