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

Posted by on .

In recent months, owing to the update for the Kindle, I guess many Kindle users may have downloaded Kindle books with KFX extension on Kindle eReader. It's a new format of Amazon Kindle, which is not very familiar to us. Now it's not only supported on the latest Kindle eReader and Kindle IOS app, but also Kindle for PC version1.19. To read Kindle KFX files on more reading app or devices, we may have the demand to convert KFX to other widely used or common format.

In this article, I will tell you how to converter KFX books to EPUB/AZW3/Mobi/PDF for details.

Method 1: Convert KFX files from Kindle for PC/Mac.
Old Solution--Degrade Kindle for PC to version 1.17
Newest and easiest solution-No need to degrade Kindle for PC/Mac from version 1.20 to 1.17 or Older Version
Method 2: Convert KFX files directly downloaded from Amazon website.

What's the KFX file and when will we get it

In August 2015, all the Kindle eReaders rolled out within the last 2 years were updated with a new typesetting and layout engine that adds hyphens, improved word spacing and ligatures to the eBooks that supports this engine require the use of the new KFX format of Amazon.

I guess the new KFX file is unknown for most of us. But do you know when and how will we get this new KFX file? In fact, not all the books we downloaded are with KFX extension. At the very beginning, if we use the latest Kindle eReader such as Kindle Paperwhite or Kindle Voyage and download eBooks supported enhanced typesetting, we will get KFX file. However, Amazon Kindle upgrade its Kindle for PC to version 1.19 on 18 Jan 2017 which also support the KFX format.

Skip to how to convert KFX file to EPUB/AZW3/Mobi/PDF from Kindle for PC/Mac.

But it’s not quite easy yet to get KFX books. Not all Kindle books support the new layout engine. Amazon has claimed that there are around 100,000 eBooks on their website which are in the new KFX format. If you want to find whether the book supports new KFX format, just look on the book's description page at Amazon. You can see a label that shows if enhanced typesetting has been enabled.

kindle books with enhanced typesettings

If we have got KFX file, when we connect our Kindle to computer via USB, we can find KFX file in Kindle "document" folder are with .kfx extension.

kfx files on kindle device

How to convert KFX books to EPUB/AZW3/Mobi/PDF

As the KFX is the new format of Amazon, currently, there is no eBook Converter including Calibre can directly convert this file to other common format. If we add or drag a KFX file to Calibre or other eBook Converter, it usually shows up an alert "unknown eBook type or unsupported eBook format". Does this imply that we cannot convert KFX books to other formats we like? Of course not, though we cannot directly convert KFX books to EPUB/AZW3/Mobi/PDF format, there are another 2 indirect methods for us to handle KFX file.

We can sync our downloaded KFX files on our Kindle via Kindle for PC/Mac(version 1.17), and we will get the common used AZW format. Or We can directly download KFX file which has already synced via our Kindle from Amazon website, then it will be saved as AZW3 or AZW file on our computer, just transfer it to Kindle via USB. If we have got common AZW or AZW3 files, then we can use a professional eBook Converter to convert KFX to EPUB/AZW3/PDF/Mobi format. Next I will tell you the 2 methods for details. But before that, we have to prepare the tool first.

Get the tool ready

To convert eBook format, we need an eBook converter to help us. Here I prefer a powerful program Ultimate eBook Converter, and want to share it with you. This tool can convert both DRM free and DRM protected KFX books to EPUB/AZW3/Mobi/PDF. It also supports batch conversion. We can convert more than 1 file at a time within a few seconds. All of these are the main reasons I like it. You can download it for free trial.

Download the tool for free

Windows Version Download Mac Version Download

Method1: Convert KFX files from Kindle for PC/Mac

Old Solution--Degrade Kindle for PC to version 1.17

Step1: Downgrade the Kindle for PC/Mac from version 1.19 to 1.17

Since the updated Kindle for PC/Mac version 1.19 supports KFX format, if you sync your downloaded KFX file on your kindle via Kindle for PC/Mac version 1.19, you will get KFX file but not the AZW book as via Kindle for PC/Mac version 1.17.

To convert the KFX books, you have to downgrade your Kindle for PC/MAC to version 1.17 or older version.

Kindle for PC v1.17 download here:
Kindle for Mac v1.17 download here:

After the installation, you have to turn off the automatic update function for Kindle for PC /Mac. Open the Kindle for PC/Mac, choose"Tools" and select " options" at its drop down list, you will find the general options. Then un-check"Autommatically install updates when they are available withou asking me." and click save.

uncheck kindle update

Step2: Sync KFX books via Kindle for PC/Mac(Version 1.17)

Login your Kindle for PC/Mac, click the "Archived Items" on the left side and find the KFX books you have downloaded on your Kindle device, then double-click its cover to download it to your computer.

downlaod kfx file via kindle for pc

After the download has been finished, you will find they are saved as common AZW format, instead of the KFX file.

sync kindle books via kindle for pc

Step3: Remove DRM from Kindle books

As most of downloaded Kindle books are protected by Kindle DRM, to convert eBook format, we'd better remove DRM first.

Run the Ultimate eBook Converter, usually if your downloaded books are saved in the default folder "My Kindle Content", they will be automatically detected and uploaded to this software. You can see them under "Kindle" icon. A really friendly design for users. No need to add books by yourself.

Next, what we need to do is only to drag Kindle books from the left side to the right frame of this program. Then all the added books will be decrypted soon. You can see the word "decrypted", which shows books have been removed DRM successfully.

remove drm from kindle books

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

After we have removed Kindle DRM successfully, now we can convert DRM free books to EPUB/PDF/Mobi/AZW3. As the image above shows, after removing DRM from AZW file, the decrypted books are Mobi or AZW3 format. We need not to convert all of them to Mobi or AZW3 files.

To convert decrypted Kindle files to EPUB/PDF, just choose "EPUB" or PDF as the output format, then click "Convert" button to start conversion.

convert kfx file to epub/pdf

When the conversion has been finished, you will see a "Succeeded" on the right side of your added books, at the same time, a window will pop up, which shows us all the converted files.

convert kfx to epub pdf mobi successfully

Newest and easiest solution-No need to degrade Kindle for PC/Mac from version 1.20 to 1.17 or Older Version

Since 14th, September 2017, we have upgraded our software to avoid the Kindle KFX directly so you do not have to degrade your Kindle for PC/MAC to older version.

Please install the latest version of Epubor Ultimate.

Download the Epubor Ultimate for free:

If your Kindle books downloaded via Kindle for PC/Mac version 1.19 or 1.20 include Kindle KFX format, when you try to remove the DRM, it will pop up a window as below.

remove Kindle DRM

Step 1: Please click on "OK', then close the Epubor software.

Step 2: Delete all Kindle books downloaded via Kindle for PC/MAC.

You can delete the Kindle book directly from the Kindle for PC as the picture instructed.

delete all books downloaded via Kindle for PC

Here is another way for you to delete the downloaded Kindle books.
For the Kindle for PC, you can delete the folder--My Kindle Content which contains all your Kindle books downloaded via Kindle for PC. You may find it here: C:\Users\your username\Documents\My Kindle Content .

For the Kindle for Mac, if you do not change the directory of Kindle content folder, you can use the following command to delete all files in Kindle content folder. Open terminal, and then copy this command rm -rf ~/Library/Application\ Support/Kindle/My\ Kindle\ Content/* to the terminal and then press on “enter" to delete all files in Kindle content folder.

Step 3: Re-download all your Kindle books via Kindle for PC/MAC.

redownload kindle books

Step 4: Run Epubor software to Remove the DRM.

remove Kindle DRM

As we can see the picture above, all Kindle Books have been decypted. To be mentioned, please follow the steps strictly and do not skip any step.

Step 5: Now you can just follow the step 4 of the old solution to convert the Kindle KFX to EPUB/PDF/Mobi/AZW3.

Method2: Convert KFX files directly downloaded from Amazon website

Except method1, 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 under "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, while we will get KFX file if we sync them via Kindle device.

downloaded kfx file saved as azw azw3

After downloading, what we need to do is only 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 Kindle DRM protected, you cannot open them via Kindle for PC/Mac or other Kindle device.

Step2: Remove Kindle DRM from Kindle e-Ink device

If we want to convert KFX to EPUB/PDF, we also need to remove Kindle DRM from Kindle e-Ink device. It's easier. Just connect Kindle to computer, drag books from the left side to the right panel. Then all the downloaded books will be decrypted.

remove kindle drm from Kindle e-ink device

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

This step is the same as step4 mentioned in the method1. Here I won't introduce again.

What a friendly and powerful program! Almost all the operation is automatic, we can convert KFX files to EPUB/PDF/Mobi with only 1 click. What's more, its conversion speed is very fast, which can really save us much time.

If you are looking for the way to convert KFX file to EPUB/PDF/Mobi, why not try these 2 methods to handle your KFX file and download the tool for free trial? Hope it will work for you.

Start my 30-days free trial

Make your KFX files freely and readable on any portable devices

Windows Version Download Mac Version Download


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

12/15/2015 01:25:08
Answer was:"Dos not support e-book format: .kfx!"
12/15/2015 19:50:51


Our software cannot deal with KFX file directly, but you can sync KFX file with Kindle for PC/Mac, or download them from Amazon website to your specific Kindle device. Then you will get AZW or AZW3 files and our software can handle them.


03/26/2016 14:54:31
Trying to use it on a 64 Bit Windows 10 machine and it just keeps hanging when trying to strip the DRM.
03/27/2016 19:20:42
How did you get the Kindle files? via Kindle for PC or download them via Amazon website to your specific device?
06/19/2016 02:10:51
Is this information/advice still valid? If I do what you recommend I still get KFX file formats downloaded, they do not come down as AZW3 files!!
09/18/2016 12:28:00
I also followed your instructions exactly and I'm still unable to convert any of my books since Amazon has updated their Kindle apps. After downloading my books from Amazon to my Kindle apps for both Windows 10 (PC) and my two android devices, I made sure I clicked on all books to archive (download) them on my PC and tablets. On my tablets, they are definitely not ending up in AZW format, they remain in KFX format. If I use the Kindle app downloaded from the Windows 10 store, there is no way to convert the 250 fragments that each book is broken/stored in. Recently I was getting around the problem by using the other Kindle app I downloaded from Amazon's website, until Windows 10 was updated (I was finally told by one of Amazon's support techs), so Amazon's PC for Kindle no longer works in Windows 10. I am now unable to sign into my Windows 10 Kindle (the one from Amazon). Only a blank sign-in box pops up. I'm no longer hopeful that Amazon will fix this problem as I've been waiting for a couple of months now and the problem still exists. I have spent HOURS searching and reading for a way to get around these problems but haven't been successful. So for now I can either wait for you to update your software to convert KFX format and/or convert the books fragments for us Window 10 users.  OR even better yet I can just change my OS to Windows 7 and get rid of this MISERABLE Windows 10!
01/19/2017 02:32:10
So if you dont actually own a physical kindle is there an emulator or some other way of getting the files in AZW format ?
02/15/2017 10:42:17
You can download Kindle for PC/Mac to sync Kindle books.
Download: http://www.epubor.com/faq.html#e106
02/25/2017 11:58:12
Amazon Kindle for PC/Windows is a new version 1.19.2 and is now using the kfx format.
01/29/2017 01:51:57
Epubor Ultimate (Trial) is not even seeing the file.
02/15/2017 10:34:22
You need downgrade Kindle for PC v1.19 to v1.17.
More details: http://www.epubor.com/faq.html#e106
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.
02/10/2017 11:16:17
Because Kindle for PC/Mac has automatically upgrade to v1.19, that makes kindle books are changed to KFX file format.
Please downgrade to v1.17 or older version.
Kindle for PC v1.17 download here:
Kindle for Mac v1.17 download here:
After downgrade to Kindle for PC/Mac, please delete and sync all books to your computer again, then run Epubor software.
Note: Kindle for PC/Mac --> tools --> options --> General, then un-check "Automatically install updates".
02/15/2017 10:33:23
You need downgrade Kindle for PC v1.19 to v1.17.
More details: http://www.epubor.com/faq.html#e106
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.

02/14/2017 23:44:03
I downloaded update to latest Epubor also installed the backdate to Kindle for PC v 1.17, but still the DRM is not removed (says "Failed".
Do I need to - in Kindle - use 'remove from collection' & also delete the recently downloaded books from Kindle Content, then re-download the books via K 1.1.7 ???
02/15/2017 10:21:28

You need find "My Kindle Content", delete all files, then sync to computer again.
You do not need to "remove from collection" or other operations.

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?
03/31/2017 18:01:39
Things will eventually sort themselves out! Let's wait and see!
03/31/2017 12:35:29
your software seems to reduce the cover jpg to fill only 1/4 of the page.
is the some way to change that?
03/31/2017 18:04:21
Screenshot the details and send to support@epubor.com
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!
04/18/2017 10:57:35
I acquired a Samsung 377A (Tab E) two weeks ago and downloaded Kindle reader for it.  Works fine except I can't use calibre to move non-amazon books to this tab.  Kindle ignores mobi, azw3, only wants KFR.  I would like a way to convert EPUB to KFR.  Any idea how to resolve this problem.  (I really hate proprietary formats!  Is there some technical advantage to KFR over other formats?)  Thanks  
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.

08/27/2017 22:32:55

This is completely bogus. The title states: "How to Convert KFX Books to EPUB/AZW3/Mobi/PDF". And then goes on to admit that it cannot directly handle or convert a .kfx file. The article simply tells you how to jump through the hoops necessary to obtain an .azw or .mobi file. All of which can be done with Calibre. Thanks for wasting my time.

Also love that the "rating" is locked to 5 stars. Way to show confidence in your software.

10/1/2017 08:58:39
This latest ePubor update has been made to alienate all of epubor's customers. It is a total cluster faaqqk. It is a exercise in frustration. Epubor should not tell their clients that their software works with the latest version of Kindle for PC. It does not. It only works with Kindle for PC version 1.17.0.
Leave a comment
YourName *
Comments UBB Editor
Home > Guide >How to Convert KFX Books to EPUB/AZW3/Mobi/PDF
  • facebooktwittergoogle plus
  • Search Epubor
mcafee badgenorton badge