How to Convert KFX Books to EPUB/PDF/AZW3/Mobi

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As the Amazon wants to build its own digital ecosystem, employing Kindle KFX DRM to all books becomes a trend. Since more and more Kindle eBooks have been encrypted with Kindle KFX DRM, Epubor Ultimate has been released as the first tool on the market to remove Kindle KFX DRM. To read Kindle KFX books on more reading apps or devices, we need to convert KFX format to other widely-used formats like EPUB and PDF format.

In this article, I am going to tell you 3 solutions on how to convert KFX books to DRM-free EPUB/AZW3/Mobi/PDF formats.

Solution 1. Convert KFX Books Downloaded via Kindle for PC/MAC

This is the most universal method, no matter you have a Kindle device or not. You just need a Kindle desktop reading app, and make sure you can read your books on your computer first.

First download Epubor Ultimate for Win/Mac to your computer.

Download Epubor Ultimate for A Free Trial

Step 1. Download Kindle for PC V2.0 or Kindle for Mac V1.40.

Kindle for PC V2.0 Download Kindle for Mac V1.40 Download

Step2. Download Kindle KFX books via Kindle for PC/Mac

Run the Kindle for PC/Mac and sign in with your Amazon account. Then all your Kindle books will be synced to the library automatically. Right-click on the books to download them to your computer. 

download Kindle books to computer

Step3. Remove DRM from Kindle KFX books

Run Epubor Ultimate, usually if your downloaded books are saved in the default folder "My Kindle Content", they will be automatically detected by this software. You can see them under the "Kindle" tab at the left column. A really user-friendly design. No need to find books everywhere manually.

Next, what we need to do is to just drag and drop Kindle books from the left side to the right blank zone. Then the DRM will be removed in a second with "Decrypted" showing.

convert kindle formats to epub

Step4. Convert KFX to EPUB/PDF/Mobi/AZW3

After we have removed Kindle DRM successfully, now we can convert the DRM-free books to EPUB/PDF/Mobi/AZW3. To convert the decrypted Kindle files to EPUB/PDF/Mobi/AZW3, just choose the format you want as the output format, then click "Convert" button to start conversion.

convert kfx to epub/pdf/mobi/azw3

When the conversion has been finished, you will see a "Succeeded" on the right side of your added books.

converting kindle kfx books succeeded

Failed to remove DRM from KCR files(on Mac Only)

If you are on Mac, some kindle books are downloaded as kcr format. Epubor Ultimate can detect and display the number of these books. See below picture.

kindle kcr format

To decrypt and convert these books, please follow this guide>>How to remove drm from kindle kcr and convert kcr to pdf.

Solution 2. Convert KFX books Downloaded from Amazon Website

Besides Solution 1, there is another useful way to convert KFX books to EPUB/AZW3/Mobi/PDF.

Step1. Download purchased books from Amazon website

Enter Amazon website, log in it with your Amazon account. Then hover over the "Your Account" drop-down menu, select "Manage Your Content and Devices", you can see all your Kindle content here. Just find the KFX books you have downloaded via Kindle device, then tap the button "More Actions", click "Download & transfer via USB".

download kfx books from amazon website

Then a following window will pop up, just select the Kindle to which you want to transfer the book. Then click "Download" button to download the book to your computer.

download KFX file from amazon website

You can see these downloaded files will be saved as AZW or AZW3 files. But you will get KFX file if you sync them via Kindle device.

downloaded kfx file saved as azw or azw3

After downloading, what we need to do is to connect our computer to Kindle via USB and transfer downloaded books from computer to Kindle's document folder.

Note: Downloaded AZW or AZW3 files can only be opened on the Kindle you have selected and are always protected by Kindle DRM, you cannot open them via Kindle for PC/Mac or other Kindle devices.

Step2. Remove Kindle DRM downloaded from Amazon Website

An interesting thing about Kindle books downloaded from Amazon website directly is that they are DRM free. Thus, there is no need to remove Kindle DRM. In case you have books downloaded from Amazon website directly protected by DRM, I will also show you how to remove DRM.

Download & run Epubor Ultimate.

Plugin the Kindle device which you select as the target device for downloading Kindle books in step 1.

Why need to plugin in the Kindle device? Because Epubor software have to detect your Kindle serial number for decrypting your Kindle books. This is the key step for removing Kindle DRM! Then drag & drop the Kindle books to the right blank zone and the books will be decrypted automatically.

remove drm from azw3

Step3. Convert KFX to EPUB/PDF/Mobi/AZW3

This step is the same as step 4 mentioned in the Solution 1. So here I won't introduce it again.

Solution 3: Convert KFX Books Downloaded via Kindle e-ink Device

If you happen to have a Kindle device, you can directly tap the book title at the library to get your Kindle eBooks downloaded. If your Kindle firmware is higher than 5.6, the eBooks you downloaded possibly in Kindle KFX format. Here you can follow me to convert KFX books downloaded via Kindle e-ink device to epub/pdf/azw3/mobi.

Step 1. Download books to Kindle E-ink device

On Kindle there are some books are saved in "Cloud", and others are saved on "On Device". So for successfully removing DRM it is necessary to make your books download to your Kindle device.

downloaded to kindle e-ink

Step 2. Plug in your Kindle e-ink device to your computer with USB

Epubor Ultimate will automatically detect your Kindle e-ink device and show all downloaded books at the left column under your eReader tab. Just drag the books from the left to the right column and the books are decrypted automatically.

remove DRM from Kindle KFX

Step 3. Convert Kindle KFX to Epub/PDF/Mobi/azw3

For converting the KFX to epub/PDF/MOBI/AZW3, just follow the guide in step 4 mentioned in the Solution 1.
Failed to remove DRM from Paperwhite 4 (Firmware 5.10.2 and above)

After you connected your device to computer and found that you failed to remove DRM, like this,

kindle firmware drm remove failed

The first solution you should do is, checking your Kindle firmware version. Amazon releases its latest software named firmware 5.10.2 and above, which makes it impossible for (both Epubor and Calibre) us to directly remove DRM from kindle devices.

If it's 5.10.2 and above, I will recommend you use Kindle for PC/Mac to sync your books and then remove DRM, or download your Kindle books via "Download & Transfer via USB".


works for Epubor and writes articles for a collection of blogs such as ebookconverter.blogspot.com.

01/31/2017 23:50:10

January 31, 2017  Tried the trial version of your software.

Since January 19, 2017, all but a few of the Kindle books from Amazon have the new KFX format.   I use Kindle for PC latest version which downloads the books with a .AZW file extension. If you look at the first few bytes of the KFX book files with a hex editor, you will see:  xDRMIONxxx.

Calibre has been updated to handle an unencrypted KFX file but the Apprentice Alf decrypter addon does not work yet.  Apprentice Alf gives identical error messages to your software so I suppose you are using the same open source decrypting code.

I will check back periodically for an update but as of this time I cannot use your product and have uninstalled it.  When there is an update available I will reinstall it and hope that a new 30 day trial is available.

02/6/2017 11:19:36
If you download the book using an old version (say 16 or 17) of the Amazon Kindle for PC then you get an AZW version that you can use.
03/8/2017 05:54:38

Hey Bob,

I was having similar issues to what you are experiencing.

I purchased an ebook via amazon but don't own a kindle and wanted to have it in pdf format. Since the kindle app is horrific and barely usable.

But I finally got around it by:

1) Navigated to the "My Kindle Content" folder and deleted all the files there.

-Keep in mind that I just had one amazon ebook in my kindle for PC library.

2) Downgrading Kindle for PC from the latest version to version Kindle for PC v1.17

-I actually downloaded it from else where cause I was a bit sceptical, though the file made available by these awesome fellows is fine.

3) Re-downloaded the ebook through the downgraded kindle for PC v1.17

4) I then opened the Ultimate converter app and just followed the instructions above..it immediately recognised and converted the book to pdf.

02/23/2017 01:37:59
This is all very well but very soon (I fear) Amazon will force an upgrade to v 1.19 and will no longer support early versions (as they did in the past) When that happens, you will no longer be able to sync your library unless you upgrade and then will end up with kfx books which the current decryption solution cannot handle (Epubor or Apprentice Alf DeDRM) calibre plugin)  Is the party over?
09/8/2018 11:41:36
Epubor will keep updating the software to remove the latest version of Amazon DRM. And the fact proves that we are the first and best eBook DRM removal developer.
04/15/2017 23:43:32

Dear epubor,

Will there be an update soon (or eventually) to epubor ultimate so that we don't have to go through these additional steps? I purchased this program to be able to convert and remove DRM almost with one click, not to have to go through this additional process.

If an update to take care of this is not in the works, I suggest that you make it clear that the program will not work with the newer KFX Kindle format so that buyers aren't misled into thinking that this will work for them as advertised and that there are additional steps they will need to go through.

I am a satisfied user of epubor ultimate so far but I do hope that an update will be made ready soon. I'm not angry about this as these things happen, but I believe that you should be working on a solution to this that doesn't require the additional steps.

Thanks so far for making a great product.

lifetime licensed user

04/26/2017 10:21:22
Thanks for your advice. We are always trying to update our software to omit these steps. But it takes time. Once we have made progress, we will inform our consumers. Best regards!
06/1/2017 10:46:03

To transfer Non-Amazon books to Kindle Android apps, please convert the books to Mobi format at first.
Then please follow the following steps:
1. Connect your Android tablet,
2, Go to the "Kindle" folder of your Android device storage. Copy and paste the MOBI books to that folder,
3, Tap the menu icon in the top right corner of Kindle app, then select "On Device" to check the transferred books.

01/8/2018 05:42:46
What about free trial? I want to try before to purcase...
01/10/2018 09:58:41
For the free trial, you just have to download it and try it! It will work smoothly. But the trial version only can convert 20% content of each book~
03/28/2018 15:44:08
WIll it be possible to convert KFX directly to epub or mobi in few years ?
03/31/2018 14:11:38
Epubor Ultimate can convert Kindle KFX to epub and mobi directly now. You are welcome to download our trial version to have a free trial.
09/8/2018 11:40:02
Successful! Thanks!
06/18/2019 10:13:08
So i downloaded and installed the kindle from the link provided and amazon asked me to verify my account using an OTP. Surprisingly the OTP was sent by my bank. So not sure what exactly happened.
06/18/2019 10:34:40
Thank you for your comments. For the one time passwords, it never should be related to your bank account but your amazon registered email. Please check this email to get the one time passwords.
07/20/2019 08:00:10
I have been using Epubor software for several years now and I can without a doubt say it's the best I've found.
Some of this work, YOu must do yourself, meaning I have an old version of a Kindle keyboard listed at Amazon, none of my Paper Whites are listed.
I deregister them soon as I buy. I have NOT upgraded any of the Paperwhites, fearing I would be left with a Reader using only the KFX extension.
Instead,when I buy my books, I make sure to check how I want to download the book, I find "Download & transfer via USB" I sent it to my desktop and from there I drag it into Epubor Ultimate! Converts and then I place in a folder or my Kindle. It's very easy to and I must say I use Epubor Ultimate everyday.It's the only software I would recommend to anyone that loves Kindle as much as I do.I use Epubor everyday as I find free books and most all need the DRM removed.I do NOT use "Kindle For Pc to store my books. If by chance you get a book with the KFX extension, simply put it into Calibre and remove it. or use the suggestion I just read on this site. I do NOT get a commission for Epubor I simply let everyone I know and some I do NOT know just how awesome this software is. Try it! :)
07/22/2019 10:57:19
We really appreciate your comments. We will always do our best to statisfy our customers.
10/15/2019 10:23:40

kindle app does not work with os 10.15

therefore, this does not work anywhere.  

10/15/2019 17:20:08

Thank you for leaving the message. Here are three methods to remove kindle drm on mac os 10.15: https://www.epubor.com/remove-kindle-drm-on-macos-1015-catalina.html
Please follow this guide to remove your kindle drm on mac os 10.15.

Any more problem, please feel free to contact support@epubor.com

09/15/2020 23:12:06
09/16/2020 08:38:38
You are welcome. If you think this article is helpful, please share it with your friends. Have a nice day.
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