Monthly Archives: September 2019

Going Back to Mobi

After receiving feedback from our users, we’re announcing that in our next update, Vellum will return to generating mobi files for the Kindle platform.

Vellum recently moved away from creating files in the mobi format, as the KindleGen utility that Vellum used to convert these files is not compatible with the forthcoming version of macOS. To generate mobi files in a manner that works with macOS Catalina, Vellum will switch to use conversion tools bundled with Amazon’s Kindle Previewer utility.

Because we have also received some positive feedback about the new Kindle.epub files, generating Kindle-specific EPUB will remain as an option. This option will also serve as a fallback in case the conversion tools in Kindle Previewer fail in the future.

This update is currently planned for October 2. In the meantime, if you need to convert Kindle.epub files to the mobi format, you can do so by opening your file in Kindle Previewer and using the Export option. If you have any questions, please contact us.

Vellum 2.6

With Vellum 2.6, you’ll find generation for Kindle to be more secure, more reliable, and much faster. That’s because Vellum no longer relies on Amazon’s KindleGen utility to convert files to the mobi format.

Instead, Vellum will now generate a Kindle-specific EPUB file.

macOS Catalina on a MacBook Pro

Ready for Catalina

If you’ve been using macOS Mojave, you’ve likely seen warnings that KindleGen is not optimized for your Mac, and won’t work with the next version of macOS. That version is Catalina, and it’s coming next month.

With Vellum 2.6, you won’t see any of these warnings, and you’ll be ready for Catalina.

Q and A

Questions & Answers

Here are some answers to questions you might have about this change:

How do I publish my Kindle ebook?
You can upload the Kindle.epub file straight to KDP. No additional conversion is necessary. Your readers won’t see any difference in the books they receive from Amazon.
How can I check my ebook beforehand?
The best way to proof your Kindle ebook is with Amazon’s Kindle Previewer, and 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.
How do I send an advanced copy to readers?
To manage your ARCs, we recommend using BookFunnel. BookFunnel can accept the Kindle.epub file generated by Vellum and will automatically convert it if necessary.

If you don’t use BookFunnel, you can export a mobi file from Kindle Previewer and send this file to your readers.

Any other questions? Contact us.

Also in Vellum 2.6:

  • You can now add an affiliate code for links to Google Play
  • Simplified approval of Restore requests for your license
  • Fixed a rare problem with incorrect page numbers
  • Improved editing margin values in regions that use a comma

To get Vellum 2.5, use Check for Updates. Or download and install Vellum from

Update 10/02/19: Mobi output is again available in Vellum 2.6.2.