EPUB to MOBI: what to do instead
Amazon retired MOBI in 2022. Here is the honest answer about converting to it — and the route that actually works.
You almost certainly do not need a MOBI file
Writing MOBI requires Amazon’s own toolchain, which cannot run in a browser. We could upload your book to a server to do it — but every other tool here runs on your device, and we are not going to make an exception that quietly sends your files away.
The better news: since August 2022, Send-to-Kindle accepts EPUB directly. Amazon converts it on their end. For any Kindle bought in the last decade, emailing the EPUB to your @kindle.com address is faster than converting and produces a better result.
Genuinely need a .mobi file for a pre-2011 device? Calibre is free, open source and runs on your desktop — it is the right tool for that job.
What to do instead
- 01 Check your KindleAnything from the Touch generation onward reads EPUB via Send-to-Kindle. No conversion needed.
- 02 Email the EPUBSend it to your @kindle.com address from an approved sender. Amazon handles the rest.
- 03 Only if the device is ancientFor a pre-2011 Kindle, use Calibre on your desktop to produce a MOBI.
Why MOBI went away
Designed in 2000 for Palm-era hardware. No embedded fonts, minimal CSS. Amazon replaced it with KF8 in 2011 and stopped accepting it for Send-to-Kindle in 2022.
The open standard, and now the format Amazon prefers you send. It is also readable everywhere else, which MOBI never was.
Questions
Why will you not just convert it on a server? ＋
Because every other tool on this site runs entirely in your browser and never uploads anything. Adding one tool that silently works differently would undermine the promise the rest of the site makes. Calibre does this locally on your desktop, and we would rather point you there.
Will my old MOBI files stop working? ＋
No. Files already on a device keep working. You just cannot email new ones to Amazon any more.
What about AZW3? ＋
Same situation — it needs Amazon’s toolchain. And the same answer: send the EPUB instead.
Are my files private? ＋
This tool runs entirely inside your browser — your file is never uploaded anywhere. It stays on your device, and closing the tab is all it takes to remove it.
Is it really free? ＋
Yes. Every tool, every file size, no account. There is no paid tier and nothing is held back.