Kindle books are protected by DRM, and Amazon's current standard eBook format is KFX. This guide explains what the KFX format is and provides the most effective method to remove DRM from Kindle KFX books and convert KFX to PDF on Windows 11 for broader device compatibility or personal backups.
1. What is KFX Format?
Amazon introduced KFX as the successor to older formats like AZW3 (KF8) and MOBI. By 2026, nearly all new and recently purchased Kindle books download in KFX format (not only .kfx suffix).
Key features of KFX:
1. Enhanced typesetting, better hyphenation, improved word spacing, and adaptive layouts.
2. Complex container structure: Often a bundle of files (encrypted main content, metadata, DRM voucher, images/fonts) rather than a single file.
3. Stronger DRM enforcement compared to older AZW3 files.
4. File extensions: Typically .kfx, but may appear as .azw, .azw8, .azw9, or even import as KFX-ZIP in tools like Calibre if not properly handled(fail to remove DRM).
2. How to Convert Kindle KFX to PDF on Win11?
Epubor Ultimate is a powerful, user-friendly DRM removal tool that effortlessly removes DRM from all Kindle books, including KFX files. Besides, it can also convert eBooks into multiple formats—EPUB, PDF, MOBI, AZW3, DOCX, and TXT—offering maximum flexibility and convenience for your reading needs.
Step 1Download and Install Epubor Ultimate
Step 2Download Kindle Desktop App from the Microsoft Store
The latest Epubor Ultimate now supports the Kindle desktop App from the Microsoft store. First, download and install the brand-new Kindle desktop app, then log in to your Amazon account and start downloading your Kindle books.
Download Kindle for Windows APP Here
Step 3Remove protection and limitation from kfx books
Launch Epubor Ultimate, and any Kindle books downloaded via Kindle MSIX app will automatically appear under the "Kindle" tab in the left sidebar. Simply drag them to the right pane to remove KFX DRM.
Kindle Files Not Shown up on Epubor Ultimate?
If you changed the default Kindle file storage folder, Epubor Ultimate cannot auto-detect your files. To fix this:
1. Sign out and sign back into the Kindle for Windows app > Re-download your Kindle files to reset the default path.
2. Go to Epubor Ultimate Settings > Kindle, click Set to default directory, and click OK. Your Kindle eBooks will immediately appear in the left sidebar.
Epubor tool supports converting kfx books even if those KFX files' location are changed in Kindle for Windows app. In that case, select "Browse" rather than "Set to default directory" to find your Kindle for Windows Content folder.
Once the decryption process is complete, a green check icon will appear next to the book title. Click the label or the book folder icon to access the DRM-free Kindle books, and its location will open on your computer.
Step 4Convert KFX to PDF
After removing Kindle DRM, choose "PDF" as the output format and click the "Convert" button to start the conversion process. Once completed, a "Succeeded" label will appear next to the book title. Click the label to access your DRM-free PDF file.
3. Is It Possible to Convert KFX to PDF without the New MS Store Kindle App?
2026 is a tough year for Kindle books' fans as Amazon is releasing its new Kindle for Windows 11 app in June and is always telling customers to use that app again and again, though, the Legacy Kindle for PC app is still working.
Amazon hasn't fully retired the legacy app, there are some reasons for us to choose the legacy app, not the store version.
If we don't own a TPM 2.0 enabled Win 11 PC, use kindle for pc legacy app;
To install the new kindle for windows app, we are required to log in with our microsoft account first. However, the legacy kindle for pc app won't.
Kindle for PC legacy app supports logging in to different regions' kindle account and change interface language. But if we want to switch to use another kindle account within the new store kindle app, we must change our computer's language and region. Any system's settings will then need a PC restart to take effect, which takes longer time for us to access our another kindle library. It's annoy.
The legacy app was a known quantity — no auto-update surprises, no ARM compatibility issues (early Store app builds had installation problems on ARM devices), and no need to fight Group Policy/registry settings just to stop unwanted updates.
The Win32 app stored downloaded books in an accessible folder on disk. The Store app runs in an MSIX AppContainer sandbox, which restricts drag-and-drop and makes it harder for external tools to reach the content folder directly.
Then the question comes out: If we keep using the legacy kindle for pc app, how to convert kfx to pdf both on win 10 and win 11?
The good news is that, Epubor Ultimate version 3.0.16.741 and above is compatible with this version of kindle app and its kfx files. You just need to click on the legacy kindle for pc app from the top right menu to locate a new interface.
Legacy Kindle for PC Version 2.9.1 App Download Epubor Ultimate for Windows Latest Version
The following steps are nearly the same as what we should follow using the win 11 version. Download kindle books offline for prepared, launch Epubor Ultimate to sync kindle donwloads, import books from left to right, select pdf as output format. Job done!
Say more, when we choose to use this version of Epubor Ultimate and the legacy Kindle app, we are allowed to manually import our kfx/azw books from "My Kindle Content" folder, while manually kfx importing from msix kindle to epubor will cause KFX error.
Amazon is updating the Kindle for Windows app weekly this year, and each update will cause either epubor tool or calibre dedrm plugin extractor stop working on latest kindle app for some days delay. No longer working since **/**/2026, waiting for a solution? Use the legacy Kindle for PC app instead, amazon won't update it anymore, we can keep using this app and matching an older version of Epubor Ultimate, as a better solution, untile Amazon disable the legacy app.
Conclusion
While KFX strengthens Amazon's ecosystem, readers can use Epubor Ultimate to own their purchases fully. Key benefits include:
1. Reading on non-Kindle devices (e.g., tablets, e-readers like Kobo/Sony/Nook).
2. Creating backups or archiving your library.
3. Converting to PDF for printing, annotations, or compatibility with apps that don't support Kindle formats.
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.
À chier!
J'ai une license à vie pour epubor KCR Converter for Mac en lifetime license. Ce logiciel n'a été installé que sur mon mac 27". La semaine dernière il me demande renouveller ma licence. Je peux la visualiser ma license sur mon compte epubor ou il est bien stipuler qu'il s'agit d'une license à vie. Mais quand je lance epubor il me demande renouveller cette license.
Le support n'a été d'aucune utilité tout en reconnaissant que j'ai une lifetime license.
Je pense qu'Epubor n'est pas une société honnête.
Please don't worry.
Hi,
I have tried all 3 methods without success.
How about giving those of us who could not get it to work remote directs hands-on support by us given Epubor Ultimate access to our laptops and desktops.
I will gladly give you full access to my laptop, so you can set it up so Epubor Ultimate works on my laptop. You or I can make a screen recording of it, which you can use as a tutorial for others to see on video. (In case I would make a screen recording of it, I can send it to you via Dropbox.)
Doing that for clients who have difficulties making it work would make Epubor Ultimate very attractive to a wide public and result in the best reviews. And it might not give you more work than replying to emails, chats via Skype, or on the above mentioned website page I copied the link to.
I hope you take up my offer to take control of my laptop to set up Epubor Ultimate right as only one of your technical experts knows how. It would be most effective
Doesn't work anymore.
Reached to the support and asked for a refund.
They sent me a link to this page instead.
Still doesn't work and my money is still gone.
This is a joke.
Thank you for using our software. Is there any error message? Doesn't work doesn't mean this software cannot handle kindle books? Our technical staff always want to help our customers to fix issue. So please describe your issue clearly and send them to our customer support via support@epubor.com. You can also reach us via livechat at every page on our website to get instant support. Please don't worry. If your choice is refund, you can also ask for refund. We will help you handle all your requests at the very first time.
Thank you for your understanding.
Thank you