MOBI Converter
FileFlip converts MOBI files into 62 other formats entirely inside your browser, using MuPDF, Pandoc and ImageMagick compiled to WebAssembly. The MOBI file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert a MOBI file?#
- Drop your MOBI file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert MOBI files online?#
Yes, because nothing is uploaded. FileFlip converts MOBI files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What happens to a MOBI file#
FileFlip converts MOBI into 62 formats with MuPDF, Pandoc and ImageMagick, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | Documents |
|---|---|
| File extension | .mobi |
| FileFlip support | Read only, so it is a source rather than a target |
| Conversions available | 62 |
| Engines | MuPDF, Pandoc and ImageMagick |
| Downloaded to your browser | 9.9 MB on the first conversion, then cached |
What is a MOBI file?#
A MOBI file holds an ebook in Mobipocket's format, a text document compressed and stored inside a Palm Database (PDB) container that Amazon adopted for the original Kindle.
There is little reason to create a new MOBI file today; it matters only for reading an ebook already saved in the format.
Convert MOBI to EPUB or PDF because Amazon no longer accepts MOBI directly and current Kindle software expects KFX or EPUB instead.
The MOBI file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
MOBI questions people ask#
What is a MOBI file?
A MOBI file is an ebook in the format Mobipocket built on top of the Palm Database (PDB) container, the same file structure Palm OS devices used for their own databases. Amazon acquired Mobipocket in 2005 and used the format for the first decade of Kindle devices.
Why won't my MOBI file work on my Kindle anymore?
Amazon announced in April 2022 that it would stop accepting MOBI files through Send to Kindle and Kindle Direct Publishing by the end of that year, converting uploads to KFX or the EPUB-derived AZW3 format instead. A MOBI file made before that change often still opens on an older Kindle, but current Kindle software and newer devices expect the file already converted.
What replaced the MOBI format?
KFX, Amazon's current Kindle format, replaced MOBI, along with AZW3 (Kindle Format 8) which Amazon introduced back in 2011. Both handle layout and typography that the older MOBI format cannot, and Amazon now converts incoming EPUB files to KFX rather than accepting MOBI as an input.
Can I remove DRM from a MOBI file to convert it?
No converter can remove DRM from a MOBI file. Mobipocket and Amazon both used encryption schemes tied to a device or account registration, and a protected MOBI file will fail to convert rather than produce readable output.