Effortless Conversion Techniques for Transforming Kindle KFX Ebooks Into ePub/PDF/Mobi with the Help of Calibre Tool

How to Convert Kindle KFX to EPUB/PDF/Mobi with Calibre

Posted by Amy Lopez on 8/17/2024 8:16:07 PM.

Important notice:

On August 8th, 2024, Amazon released Kindle for PC version 2.4.1. Unfortunately, this update prevents the removal of Kindle DRM. As a result, Kindle books downloaded via Kindle for PC 2.4.1 or later, and Kindle for Mac 1.40 later, cannot be decrypted by Epubor Ultimate or the Calibre DeDRM plugin.

Solution:
• For Windows users: Download Kindle for PC version 2.4.0 and re-download your Kindle books to remove DRM.
• For Mac users: Download Kindle for Mac version 1.40 and re-download your Kindle books to remove DRM.

Ultimate Solution:
If you own a Kindle e-ink device, you can download your Kindle books through the ‘Download & Transfer via USB’ option on the Amazon website. This method provides AZW3 files, which can be decrypted using Epubor Ultimate.

Great news for Calibre users! The latest version of the DeDRM plugin now supports the KFX format, making it easy to import KFX books into Calibre. This allows you to remove KFX DRM for creating backups and converting them to other formats. In this article, I’ll show you step-by-step how to remove DRM from KFX books and convert them to Mobi, EPUB, or PDF.

1. How to Convert Kindle KFX to EPUB/PDF/Mobi with Calibre

The DeDRM Calibre plugin is intended to help anyone looking for free software for removing DRM from their purchased Kindle KFX ebooks. But we have to admit that the biggest inconvenience about using Calibre to remove DRM is that you have to install De-DRM Plugin and KFX Conversion Input Plugin to Calibre first. And this is also the most difficult and also indispensable part to use Calibre to convert DRMed KFX books to EPUB/PDF/TXT…

Step 1Download Calibre to your computer and launch it.

Step 2Download DeDRM_tools (v10.0.9) and KFX Conversion Input Plugin to your computer.

Remember to unzip the DeDRM_tools plugin package, or you won’t be able to load the plugin to calibre successfully.

Step 3Load DeDRM Calibre Plugin and KFX Conversion Input Plugin to Calibre.

Open calibre’s Preferences dialog. Click on the Plugins button. Next, click on the Load plugin from file button.

Navigate to the DeDRM_tools folder and, find the file DeDRM_plugin.zip. Click to select the file and select Open.

Click Yes in the ‘Are you sure?’ dialog box. Click the OK button in the ‘Success’ dialog box.

Then repeat the same operation to load the zipped KFX Input folder to Calibre(You do not need to unzip KFX input plugin).

And the DeDRM plugin will be displayed under File type.

The KFX Input plugin will be displayed under ‘Conversion input’.

Step 4Add Kindle KFX books to Calibre by clicking Add books in the tool bar.

You need to download KFX books with Kindle for PC/Mac or Kindle e-ink Reader first, then add KFX books from ‘My Kindle Content’ folder or the Kindle’s Document folder to Calibre manually. The book will be decrypted soon after you add it to Calibre library.

The KFX books downloaded with Kindle for PC/Mac will be saved in .azw format.

While the KFX books downloaded with Kindle device will be saved in .kfx format.

When you add KFX books to Calibre library, please make sure that your know exactly where your downloaded KFX books are stored on your computer.

If your KFX books are downloaded to your computer with Kindle for PC/Mac, you need to add KFX books to Calibre library from ‘My Kindle Document’ folder.

Step 5Convert KFX to EPUB/Mobi/PDF

Click Convert books in the tool bar and choose EPUB/Mobi/PDF/AZW3/TXT/DOCX… as the output format and click OK to start the conversion.

The book will have two formats for you to choose from after the conversion.

2. How to Convert Kindle KFX to EPUB/PDF/Mobi without Installing Plugins

Epubor Ultimate is a powerful tool designed to effortlessly remove DRM protection from Kindle books while offering seamless conversion capabilities for ebooks into various formats such as EPUB, PDF, MOBI, AZW3, DOCX, and TXT.

Step 1Download and install Epubor Ultimate

Download and Install Epubor Ultimate for free:

Step 2Download Kindle Books via Kindle for PC

Kindle books downloaded via Kindle for PC version 2.4.0 above, or Kindle for Mac version 1.40 above, are not supported by Epubor Ultimate. To remove DRM, you must download your Kindle books using Kindle for PC version 2.4.0 or Kindle for Mac version 1.40.

Download Kindle for PC 2.4.0 here

Download Kindle for Mac 1.40 here

After installing the Kindle app and signing in to your Amazon account, you can start downloading Kindle books by tapping on the book cover.

Step 3Remove Kindle DRM

Launch Epubor Ultimate, your Kindle books, downloaded via Kindle for PC, will be automatically imported and displayed under the Kindle tab. Alternatively, use the ‘Kindle’ tab in the toolbar to auto-detect newly downloaded Kindle books. Select book titles on the left side bar and drag & drop them to the window on the right to remove Kindle DRM.

Ultimate Solution: If you own a Kindle e-ink device, you can download your Kindle books through the ‘Download & Transfer via USB’ option on the Amazon website. This method provides AZW3 files, which can be decrypted using Epubor Ultimate.

Step 4Convert Kindle Books to EPUB/PDF/AZW3/MOBI/TXT

Choose PDF/EPUB/Mobi/TXT/AZW3 as the output format from the drop-down menu, select either EPUB or PDF as your desired output format. Then click the ‘Convert’ button to initiate the conversion process.

After the conversion process is complete, you can find the converted files by clicking on the book folder icon located in the lower right corner of the software.

For more intuitive instructions, here is a video tutorial:

For Kindle ebooks downloaded on Mac computer may be in kcr format. There are two ways to remove drm from KCR and convert kcr to pdf .

3. Calibre VS. Epubor Ultimate

Calibre is an open source freeware ebook library manager. It is the best tool around for keeping track of your ebooks. The DeDRM plugin for Calibre provides a free way to remove DRM from your Kindle and Adobe DRM ebooks. Though Epubor Ultimate is a paid software, it has absolute advantage over Calibre. First of all, you don’t have to download the DeDRM plugins and the KFX Conversion Input Plugin. This could be a pain in the ass if you are a tech newbie. Second, Epubor Ultimate supports removing DRM from KFX books downloaded from Kindle e-Ink Reader. Third, Epubor Ultimate can automatically detect all of your downloaded Kindle books, so you don’t need to add your downloaded KFX books to the software manually.

In a word, Calibre is not as easy as Epubor Ultimate, it’s a little difficult to handle for some people who is not skillful. Epubor Ultimate can definitely save you a lot of trouble by converting DRMed books to Mobi/ePub/PDF… So it totally worths your money. And if you are not satisfied with Epubor software, you can get your money back within 30 days after you place the order.

Conclusion

When comparing Calibre and Epubor Ultimate, both tools have their own advantages. However, Epubor Ultimate is more efficient and convenient for removing DRM from KFX books and converting them to other ebook formats. If you are not tech-savvy, we strongly recommend using Epubor Ultimate, as it allows you to solve the problem smoothly.

Download Epubor Ultimate for Free

Suggested reading

Amy Lopez crafts informative articles on eBooks and eReaders, uncovering optimal methods to enhance your eBook reading experience, and eagerly shares her findings with you.

SHARING IS GREAT!

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52 Comments

rintintin

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

06/23/2018 22:18:17

V. helpful! Worked like a charm – TY!

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MikeF

Re:rintintin

02/6/2023 20:49:52

I don’t see any new Plug-Ins:
-De-DRM is 7.2.1 from 2022
-KFX-Input is 1.50.0 also 2022
Neither of them work to convert KFX files.

It would appear that Amazon are now checking the Kindle for PC version. I have a book from 2023 and it will not download into my KfPC V1.17.
J Howell states somewhere that he has still cracked KFX conversion.

Any chance in the near future of sorting out KFX conversion in Calibre?

Epubor

Re:MikeF

02/13/2023 11:12:57

For the calibre technical issue, please contact calibre to get the further support.

Yoop

Re:MikeF

07/4/2023 06:15:40

AFAIK, there’s no way to convert Kindle books that are part of the current Kindle (06-2023).

Epubor

Re:Yoop

07/4/2023 11:00:36

Hello,

For the ebooks published in 2023, here are 2 solutions to solve this problem:
1.If you have any Kindle device (kindle fire or kindle e-ink device) registered with your Amazon account.
Please download the Kindle books via “download and transfer via USB” and then remove kindle drm with epubor ultimate.
Here is the detailed guide: https://www.epubor.com/how-to-remove-drm-from-kindle-kfx-ebooks.html#meth4

2. If you don’t have a Kindle e-ink device, we recommend our new product Kindle Converter to decrypt and convert the Kindle books published in 2023. please learn more here:https://www.epubor.com/kindle-converter.html
User guide: https://www.epubor.com/kindle-converter-user-guide.html

Rolf

Re:MikeF

12/29/2023 20:11:58

Same here, with Calibre 6.0.0
cannot convert because of DRM.

the 2 extensions are installed

horst

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

12/5/2018 04:56:37

that worked great

Epubor Iris

Re:horst

12/5/2018 08:47:13

We are glad to know that this method works great.

hub

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

12/6/2018 19:45:17

great, thank you very much!

Epubor Iris

Re:hub

12/7/2018 15:21:07

Thank you for your comments. We are glad to know this article can help you.

dave

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

12/19/2018 19:45:13

no longer works leaves file in KFX-ZIP and still with drm on it

Epubor Iris

Re:dave

12/20/2018 14:13:32

Please ensure you are using the Kindle for pc/mac version before 1.25 to download the Kindle kfx ebooks. Then run Epubor Ultimate to remove the drm, I am pretty sure it works fine. If you can not figure out how to do it, please contact our customer service support@epubor.com to get more assistance.

voodoo

Re:Epubor Iris

01/29/2019 05:14:44

yup- doesn’t seem to work with v1.25 - i get same result as above. DRM not removed

Epubor Angel

Re:voodoo

01/29/2019 14:29:32

Hello,

Yes after Kindle desktop v1.25 and firmware 5.10.2 released, amazon kindle changed their drm scheme technology, which results in drm removing failed.

You’d better downgrade your Kindle for PC/Mac to 1.24(1.23) and STOP auto-update.

Then, use either Epubor or Calibre to help you.

Johan N

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

05/9/2019 04:54:56

Thank you very much for the guidelines and tips given. The end results is marvelous. Now I can read my Kindle books easily on my android phone.

EPUBOR

Re:Johan N

05/9/2019 10:21:56

Glad to know that you like this guide. If you think this guide is helpful, please share it!

lUKE

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

06/4/2019 18:44:52

Hello,
I have followed the process above. However, when I am going to convert the file kindle, I received the message “ cannot covert the ….” This book is locked by DRM…

What did I do wrong?

ps: I had downloaded the last versions of DeDRM_tools and KFX Conversion Input Plugin.
I am going to enrol a Master and most of the books are in Kindle format.

Thank for your help.

Epubor

Re:lUKE

06/5/2019 09:00:00

If there is the error message “..locked by Kindle drm”, that means your book are not decrypted. Please follow the instruction again. I know this is a little bit difficult. Also, you can download Epubor Ultimate to remove Kindle drm and convert it to any other format. This software is easy to use.

Reinaldo Luckman

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

06/24/2019 08:09:15

Thanks, man. Worked like a charm. As I dowloaded from my eInk device, just configured the plugin with the serial number and bam! ePub done! :)

Iris Yan

Re:Reinaldo Luckman

06/24/2019 08:49:58

Thank you for your comments.
Have a nice day!

Preethi

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

07/26/2020 10:19:38

Awesome. Thanks for this guide. I was able to finally get it to work!
For me, 2.24 version didn’t work. I tried 1.17 version, the file was automatically shown in Calibre as AZW instead of KFX-ZIP. Though I had to disable my Windows Defender Firewall and Security Software to be able to successfully download DeDRM 6.8, KFX and Kindle 1.17 version. Now, I’m a happy camper… Enjoy

Alejandro

Re:Preethi

08/29/2020 14:48:41

Tx it’s work

Epubor

Re:Alejandro

08/31/2020 11:16:31

Thank you for your feedback. That’s glad to hear.

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Vas

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

10/15/2020 16:02:31

Please help. When i tried to install DRM tools this message i got :

calibre, version 5.2.0
ERROR: Unhandled exception: <b>SyntaxError</b>:invalid syntax (calibre_plugins.dedrm.__init__, line 168)

calibre 5.2 embedded-python: True is64bit: True
macOS-10.15.7-x86_64-i386-64bit Darwin (‘64bit’, ‘’)
(‘Darwin’, ‘19.6.0’, ‘Darwin Kernel Version 19.6.0: Mon Aug 31 22:12:52 PDT 2020; root:xnu-6153.141.2~1/RELEASE_X86_64’)
Python 3.8.5
OSX: (‘10.15.7’, (‘’, ‘’, ‘’), ‘x86_64’)
Interface language: None
Successfully initialized third party plugins: Gather KFX-ZIP (from KFX Input) (1, 34, 0) && Package KFX (from KFX Input) (1, 34, 0) && KFX metadata reader (from KFX Input) (1, 34, 0) && KFX Input (1, 34, 0) && Set KFX metadata (from KFX Output) (1, 44, 0) && KFX Output (1, 44, 0) && Obok DeDRM (6, 7, 0)
Traceback (most recent call last):
File “calibre/gui2/preferences/plugins.py”, line 317, in add_plugin
File “calibre/customize/ui.py”, line 472, in add_plugin
File “calibre/customize/ui.py”, line 61, in load_plugin
File “calibre/customize/zipplugin.py”, line 282, in load
File “importlib/__init__.py”, line 127, in import_module
File “<frozen importlib._bootstrap>”, line 1014, in _gcd_import
File “<frozen importlib._bootstrap>”, line 991, in _find_and_load
File “<frozen importlib._bootstrap>”, line 975, in _find_and_load_unlocked
File “<frozen importlib._bootstrap>”, line 671, in _load_unlocked
File “calibre/customize/zipplugin.py”, line 174, in exec_module
File “calibre/customize/zipplugin.py”, line 170, in get_code
File “calibre_plugins.dedrm.__init__“, line 168
print u” v: Copying needed library files from plugin’s zip”.format(PLUGIN_NAME, PLUGIN_VERSION)
^
SyntaxError: invalid syntax

Epubor

Re:Vas

10/16/2020 17:24:52

Yes, that’s because the latest calibre version 5.0 or later is not compatible with the calibre drm-removal plugin. Please follow this guide to get this problem fixed: https://www.epubor.com/solutions-to-calibre-dedrm-plugin-not-working.html

Mystique

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

11/23/2020 04:22:04

I downloaded the DeDRM Calibre Plugin and KFX Conversion Input Plugin, and installed them to Calibre. I’m running Calibre 3.30

I downloaded a Kindle Book (using Kindle 1.26.1), and located the .AZW file.

When added to Calibre, the book cover now appears, and the format is KFX-ZIP. When I try to convert to ePub, I get an error that the book contains DRM and cannot be converted.

What am I missing? Thanks!!

Epubor

Re:Mystique

11/23/2020 09:20:39

Thank you for asking. To remove drm from kindle books, please download kindle books via kindle for pc 1.24 or earlier version.

Epubor

Re:Epubor

11/23/2020 09:21:44

Here is the way to downgrade kindle for pc to older version>> https://www.epubor.com/how-to-downgrade-kindle-for-pcmac.html

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Mystique

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

11/23/2020 22:01:13

Thanks, Epubdor…but there’s a highlight banner on the downgrade instruction page that say “Notice: If you are on Mac Catalina 10.15, downgrading kindle to 1.23 or older will not work any more”

Epubor

Re:Mystique

11/24/2020 08:53:57

Thank you for contacting us. If you are mac catalina, please follow this guide to remove kindle drm:
https://www.epubor.com/remove-kindle-drm-on-macos-1015-catalina.html
https://www.epubor.com/patch-kindle-for-mac-on-mac-catalina.html

Loulou

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

03/1/2021 02:48:11

Hello, epubor didn’t work! and I installed the DRM plug-in in Calibre and that ddn’t work either :(

jhgh

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

04/10/2021 20:18:22

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Adam Quinn

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

09/22/2021 14:04:40

Sadly all failed for me :/

Epubor

Re:Adam Quinn

09/27/2021 09:43:20

Have you tried the Epubor Ultimate? If you have any issue with Epubor Ultimate, please feel free to contact us via support@gmail.com .

bachoi

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

06/21/2022 22:53:59

Absolutely FAIL!!! it does not solve the ddm

TheChosenOne

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

08/24/2022 05:52:19

For those of you who are still struggling rent your books through a digital library and go ahead download adobe digital editions 4.5. Once you rented click on download epub make sure the book is going to adobe digital. Calibre works perfectly with adobe, I’ve used kindle pc 4 months ago with no problem and now kfx has been implemented on all books calibre fails to dedrm.

symcoxkd

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

01/6/2023 05:37:27

“A terrific good news for loyal Calibre users is last week Apprentice Alf released a new version of the DeDRM tools with added support for KFX format, so now you can easily import KFX books to Calibre to remove KFX DRM in order to create backups and convert them to other formats.”

The link to the dedrm tool on this page references 7.21 from 2021 and does not include kfx, despite the blurb.

Epubor

Re:symcoxkd

01/16/2023 10:43:53

Thank you for your message. You can use this link to get the latest dedrm plugin: https://github.com/noDRM/DeDRM%5Ftools/releases/tag/v10.0.3

John

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

01/7/2023 06:34:11

I can’t find the updated version of DRM-tools either.

Epubor

Re:John

01/16/2023 10:45:59

Thank you for your feedback. We’ve updated this article, please click the link in this article to get the latest dedrm tool.

Bob C.

Re:Epubor

01/25/2023 04:39:08

I installed the latest version of DeDRM (10.0.1?) and the KFX plugin. Both installed fine, but an Amazon book I bought and downloaded today isn’t “cleaned” after being loaded in Calibre, so it wouldn’t convert(message: Has DRM). I’m using the latest Kindle for PC (1.39), and version 3.48 of Calibre. Any thoughts?

Robert

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

03/12/2023 09:32:06

This applies to books from Kindle Unlimited

The DeDRM tools with added support for KFX format is NOT working in Calibre with new books from Kindle Unlimited. It will not strip the DRM.
Epubor Ultimate is also not working. When downgrading from version 1.35, you cannot save the book into your Kindle for PC anymore. Will there be upgrade or they already win? :-)

Epubor

Re:Robert

03/13/2023 16:19:06

For now, there is no way to decrypt the kindle for pc 1.35, please use the older kindle for pc to download kindle books and remove drm.

Thomas F

Re:Epubor

05/10/2023 07:37:27

“for now there is no way to decrypt the kindle for pc 1.35…”

well why did I pay for Epubor Ultimate and now have no way of removing drm from my existing books because it tells me that it will no longer download my books that I am purchasing unless I use a newer version of Kindle for pc?

kindle for pc is up to v1.36 and you still have not found a workaround?

Epubor

Re:Thomas F

05/10/2023 09:58:44

Hello, thanks for your comment. Don’t worry, luckily we have researched a new method to solve this problem. Once the new solution is launched, we’ll inform you as soon as possible, please keep an eye on the updated information from our website.

Any other questions, please feel free to contact us.
Best regards,
Epubor Team

Olga

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

04/23/2023 05:12:27

The link to the KFX plugin in your page did not work, it brings you to a page that says “invalid attachment”

I tried to download it somewhere else. And did download some KFX input plugin, but when I tried to import it into calibre there was no plugin at all that I could upload. I could not find any workable one. I am using Mac I don’t know if it has something to do with it.

I would be happy for some help. Best regards

Epubor

Re:Olga

04/23/2023 10:30:06

Hello, thanks for your comment. We’ve updated the link to download the KFX input plugin in this article. Please download the files from the correct place. As for Mac, please open Calibre’s Preferences dialog at the top. Then click on “Preferences”. Next, click on the green button of plugins at the bottom. Then blue Load plugin from the file button at the right bottom to upload the plugin files you downloaded.

Please try again, if there is still the same problem, please feel free to contact us via support@epubor.com . Thank you!

Michael

Re:How to Convert Kindle KFX to Epub/PDF/Mobi with Calibre

08/7/2023 05:55:12

Did not work for me. The DRM cannot be removed… Still cannot convert kfx… stuck with kindle books on myphone- cannot read aloud and i used to like to listen to them on long drives. Too bad the feature was removed- I will probably not use kindle much more after this

Epubor

Re:Michael

08/8/2023 11:44:59

Hello, thanks for your comment.

If you can’t remove drm with Calibre, please try our Epubor Ultimate, it allows you to decrypt and convert your Kindle books.

Any other question, please feel free to contact us via support@epubor.com .

Best regards,
Epubor Team

Some Skills

Effortless Conversion Techniques for Transforming Kindle KFX Ebooks Into ePub/PDF/Mobi with the Help of Calibre Tool