EPUB to MOBI converter software refers to applications and tools used to change the format of an eBook from EPUB (the universal open standard used by Apple Books, Kobo, and Google Play) to MOBI (the older, proprietary eBook format originally used by Amazon Kindle devices).
However, before diving into the available software, there is a critical compatibility update to keep in mind: Amazon has completely phased out support for MOBI files. Amazon KDP ended fixed-layout MOBI support on March 18, 2025, following their 2021 termination of reflowable MOBI files. Modern Kindle e-readers now accept EPUB files directly through the “Send to Kindle” service and convert them internally to more modern formats like AZW3 or KFX. You generally only need a dedicated MOBI converter if you are managing sideloaded books on legacy, offline Kindle hardware.
If you still need dedicated software to handle these files, the best tools fall into three main categories: 1. Open-Source & Desktop Software