Kindle Ebook Format | Vellum Help

Kindle Ebook Format

Vellum can generate Kindle ebooks in either the mobi or epub format.

You can change which format Vellum will generate using the Generation pane in Vellum ▸ Preferences:

The Generation Pane in the Preferences dialog

You can upload either format directly to Amazon KDP.

MOBI Format

Amazon’s MOBI format is the easiest format to use if you need to send your ebook directly to Kindle readers.

To generate a MOBI file, Vellum requires Amazon’s Kindle Previewer application. If you don’t have it already, you will need to download and install it.

EPUB Format

Generating a Kindle.epub file is significantly faster than generating a mobi file. It can be uploaded directly to Amazon, and your readers won’t see any difference in the books they receive.


You should always proof your Kindle ebook with Amazon’s Kindle Previewer, as it’s the only way to view your book with Enhanced Typesetting before you publish. You can open a Kindle.epub file directly in Kindle Previewer.

Advance Reader Copies

To send a Kindle ebook file to a reader, you will need a file in the mobiformat. You can either Export one from Kindle Previewer, or switch Vellum to generate mobi instead.


If you use BookFunnel to manage your ARCs, then you can upload the Kindle.epub file directly.