Will Kindle Comic Converter Still Work on macOS 28?
macOS 28 removes Rosetta, and KindleGen, the Intel-only tool KCC needs for MOBI output, will stop running on Apple Silicon. What still works, and your options.
If you convert manga on a Mac with Kindle Comic Converter, here is the plain version. KCC itself is fine: it runs natively on Apple Silicon and its maintainer keeps it current (10.3.0 already supports macOS 27). The part with a countdown on it is MOBI and AZW3 output, because that path runs through KindleGen, an Intel-only Amazon binary that needs Rosetta 2 to run on an Apple Silicon Mac. macOS 27 uninstalls Rosetta (you can put it back). macOS 28 removes it entirely, and there is no putting it back.
EPUB output does not use KindleGen at all, so KCC's EPUB path keeps working. So does anything that runs in a browser instead of on your Mac.
Short version
MOBI/AZW3 conversion on a Mac depends on KindleGen, which Amazon only ever built for Intel. Rosetta 2, the layer that lets Intel programs run on Apple Silicon, is being retired: macOS 27 uninstalls it, macOS 28 removes it. After that, MOBI/AZW3 output in KCC stops working on a current Mac. Your options: output EPUB instead (works today, and Send to Kindle has accepted EPUB since 2022), keep an Intel machine or an older macOS around, ask Amazon for Apple Silicon builds, or convert in the browser where there is nothing to install.
Why a manga converter depends on a discontinued Amazon tool
KCC does its own image work: resizing pages for your device, fixing contrast for e-ink, keeping manga right to left. But it cannot write Amazon's MOBI and AZW3 formats itself. For those, it calls KindleGen, Amazon's own command-line converter. Amazon stopped offering KindleGen as a standalone download years ago; today you get it by installing Kindle Previewer and letting KCC find the binary inside it.
KindleGen was only ever built for Intel processors. On an Apple Silicon Mac (anything with an M-series chip), Intel programs run through Rosetta 2, Apple's translation layer. That has worked quietly for years, which is why most people have never had to think about it.
Apple is now retiring Rosetta. Upgrading to macOS 27 (Golden Gate) uninstalls it, and KCC 10.3.0 will prompt you to reinstall it. macOS 28 removes it entirely.
KCC's own maintainer said it plainly in the KCC 10.3.0 release video: "macOS 28 will remove Rosetta entirely, so KCC might stop working then", because Kindle Previewer, Kindle Create and KindleGen are all still Intel-only apps. His ask, which we would echo: tell Amazon you want native Apple Silicon versions, through the feedback menu in Kindle Previewer or Kindle Create, or Amazon's contact form. This is not something the KCC project can fix with a release. Only Amazon can rebuild Amazon's binary.
To be clear about scale: in the KCC 10.2.0 video the maintainer shared download stats, with about 18% of KCC users on modern macOS and, of those, 85% on Apple Silicon. That is a lot of Macs heading toward macOS 28.
What this does and does not break
| You use KCC for | After macOS 28 |
|---|---|
| EPUB output (Send to Kindle, most modern workflows) | Keeps working, no KindleGen involved |
| KEPUB for Kobo, CBZ output | Keeps working |
| MOBI/AZW3 output (KindleGen) | Stops working on Apple Silicon |
| KCC on Windows or Linux | Unaffected |
| A browser-based converter | Unaffected, nothing is installed |
The honest context here is that MOBI matters less than it used to. Amazon dropped MOBI from Send to Kindle in 2022; EPUB is the format it accepts now. If you convert for a reasonably recent Kindle, EPUB output already serves you better, and that path survives every macOS release. Where MOBI/AZW3 still earns its keep is old Kindles that predate EPUB support (see What is an AZW3 file for where the formats sit).
Your options, honestly
- Switch your output to EPUB. Works in KCC today with no KindleGen installed, and it is what Send to Kindle accepts anyway. If you were only making MOBI out of habit, this costs you nothing.
- Keep a machine that can still run KindleGen. An Intel Mac, a Mac held back on macOS 26 or 27 with Rosetta reinstalled, or a Windows or Linux box. This works, but it is a countdown, not a fix: old OS versions age out of security updates.
- Ask Amazon for Apple Silicon builds. The KCC maintainer's own request. If enough Kindle Previewer feedback asks for it, the deadline disappears for everyone.
- Convert in the browser. MangaConverter runs KCC's engine as a web app: same device profiles, same right-to-left handling, Kindle-ready EPUB out, with a live preview. There is nothing to install, so there is nothing Rosetta-shaped to break, on macOS 28 or anything after it. It works on a phone, too.
None of this is a knock on KCC. It has been the reference tool for this job for over a decade, it is actively maintained, and the wedge here is Amazon's abandoned binary meeting Apple's platform cleanup. But if your Mac is going to be on macOS 28 eventually, it is worth knowing which of your tools come with you.
Frequently asked questions
Does Kindle Comic Converter work on Apple Silicon today?
Yes. KCC ships a native Apple Silicon build and supports macOS 27. Only the MOBI/AZW3 step depends on Rosetta, and on macOS 27 you will be prompted to reinstall Rosetta for it.
Do I need KindleGen at all?
Only for MOBI and AZW3 output. KCC's EPUB, KEPUB and CBZ output never touches KindleGen, and EPUB is what Send to Kindle accepts anyway.
When does Rosetta actually go away?
macOS 27 uninstalls it on upgrade but lets you reinstall it. macOS 28 removes it entirely, with no reinstall option.
Will a web converter really keep working?
Yes. A web converter runs in the browser itself, not as an Intel binary installed on your Mac, so a macOS upgrade cannot take it away. If it runs in Safari, it runs on macOS 28.