[reading] Kindle file format & encryption changes on Mac/PC apps


If you use Calibre to convert and back up your eBooks, be aware that Amazon have changed the format and the DRM scheme on their books, replacing AWZ3 with KFX as the default for the Mac and PC Kindle apps.

In theory, if you have an e-Ink Kindle device you can download the AWZ3 files from the Amazon website for a USB transfer and then convert them, but I'm seeing multiple failures from books, especially recent ones.

Another route is to revert the Kindle App back to the old version, but you'll need to find a safe download version as Amazon isn't hosting the old (pre-1.19 and KFX format) version of the app.

There is a thread on the new format here: https://www.mobileread.com/forums/showthread.php?t=283371

If anyone has got around this on a Mac and wants to share, please do! No doubt that parity will be restored, the question is well
I've not yet upgraded my Kindle for Mac app (I turned off the auto-update option) - I'll be looking into that after Continuum. I've upgraded my iPad & iPhone apps, but not the Kindle for Mac as that is where I do my archiving and transfer to device (the Icarus) as ePub files. Effectively, the Kindle apps are about 1/3 of my ebook library so I use the Icarus as my primary reading device, and Calibre acts as my primary ebook archive. I also catalogue everything on LibraryThing - that's my primary reference, although I've yet to finish cataloguing my RPG PDFs (fortunately, if I've got wi-fi, I can check my iCloud which is where they all live).

There's a new version of DeDRM from Apprentice Alf (link at https://apprenticealf.wordpress.com/) which I shall have to install before I upgrade. Alternatively, I shall use the KFX input plug-in and auto-convert to ePub (which will mess up any graphic novels I have - which get read on the iPad only so it shouldn't matter). Whatever you do, don't get suckered into shelling out for epubor as it's an uncredited rip-off of Apprentice Alf.


Hi Maddz,

Is there an easy to use solution yet that doesn't involve having to hack around and either downgrade the Kindle build on my Mac or compile stuff?



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I am still on a 3rd gen Kindle with a spare in the cupboard. I'll grab the new deDRM.
But my reading for pleasure is now so impacted by my reading for work that this has very low priority for me these days.
Hi Maddz,

Is there an easy to use solution yet that doesn't involve having to hack around and either downgrade the Kindle build on my Mac or compile stuff?

Kovid Goyal’s Calibre coupled with Apprentice Alf. Neither require compilation. It’s pretty seamless - open up your Kindle app, do a sync and download any new files, open up Calibre and add the newly downloaded files from My Kindle Content. I usually convert to epub at that point and clean up Amazon’s crappy metadata (including adding ISBNs), then log the book on LibraryThing and transfer to the Icarus.

I will admit that having started working again in August I haven’t yet upgraded my Kindle for Mac, although I’ve downloaded the new Apprentice Alf. I’ve also just been offered a permanent position so I’ll be commuting to London for the foreseeable future.

(Memo to self: locate the old KfM installer and stash it in iCloud drive before I upgrade....)
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OK, I have a dmg for Kindle for Mac dated July 2015. I'm not sure of the exact version number it installs, but that would be pre-KFX. I suspect it's an older version auto-updated to 1.17 when I killed the auto-update. I know when I had my hard drive replaced last year I had to revert to 1.17 because the new install had auto-update on (luckily, I was able to overwrite the app from Time Machine).

Right, it's 1.12 which would have been auto-updated to 1.17. Not sure what happens if I turn on auto-update - whether the updates are incremental or not. It didn't update immediately, so I may have to go through the app store... Just as well I checked - the preferences are the same for both versions - to setting the older to auto-update also sets the new to auto-update as well. Guess I won't fiddle with it until I positively have to. I may experiment on the MacBook instead (quite apart from anything, it's a newer version of the OS), but I'm going to have to make copies of the Calibre DB files as well as My Kindle Content into iCloud.

In any case, it looks like the older KfM won't work for much longer as it's 32-bit and Apple will be discontinuing 32-bit support after Mojave, so it looks like I'll be experimenting in the run-up to Christmas with clean installs on the MacBook.
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After some fiddling around on the MacBook:

Installed the latest Kindle for Mac and (eventually) imported all 948 kindle books I own or have access to, Note that you should go to Content & Devices/Devices and check any shared library options have the radio button checked before trying to sync and download. Then go to content and work your way through 200 at a time and send it to your newly registered device.

Now download Calibre, and go to Apprentice Alf and download the DeDRM tools. Unzip the DeDRM tools, go to Calibre\Preferences and find the Plug-ins preferences (this is in the main Calibre menu item \ Preferences at the top left not the Preferences menu item at the top right). Click the install from file button (bottom right-hand corner), navigate to your unzipped DeDRM tools file and go to the Calibre plug-in directory and select the zip file in there, click OK.

Go to the Preference menu item (top right), choose plug-ins and install the KFX Input plug-in and any other plug-ins you find useful.

Click the Add Books button and select the from multiple directories option (otherwise you will have to add all your newly imported Kindle books one at a time...)

Move your newly imported book files to the cloud because your hard drive is now full (better, don't download all those graphic novels!)