Calibre-Web is a web app that offers a clean and intuitive interface for browsing, reading, and downloading eBooks using a valid Calibre database.

Now, we will have to first download two plugins – DeDRM and KFX. The DeDRM can be downloaded from the following link, while the KFX plugin can be installed from the Calibre app itself (refer to step 4).

Step 5: Load Kindle books and remove DRM protections

• Now that all the plugins are installed, simply drag and drop the downloaded AZW3 files (under Documents > My Kindle Content) to your Calibre library.
• Calibre will automatically remove the DRM for these books. To be sure, click on Convert books at the top.
• Select an output format at the top right corner.
• And click OK.
  • If your books are converted without any error messages, then you have safely removed the DRM from them. You can now save them wherever you like. To do so, right-click on a file and Save to disk.
• And select a folder.
• All your converted and DRM-free files will be in this folder.

It is ideal to get the latest version of Calibre to DeDRM books. But Calibre alone won’t be able to do so. You will need the DeDRM and KFX plugins as well to fully DeDRM your Kindle books.

Use a Kindle Paperwhite (v5), then open Amazon, manage digital purchases, and download and transfer book files. Save them to the PC, then drag and drop into Calibre.

I used to prefer kobodl because it's standalone, which means you don't need other proprietary software like Adobe Digial Editions or Kindle for PC (that I can't use on Linux). However, I have since discoverd a way to do this with Calibre and 2 plugins:

Leseratte10/acsm-calibre-plugin - A plugin that can read Adobe Digital Editions files that Kobo web download produces.
noDRM/DeDRM_tools - The popular DRM removal plugin.
Now you can just download the .acm file from your book list on Kobo.com and load it into Calibre desktop!

At some point you will run into the situation where you have transferred an ebook in .mobi format to your Kindle Fire and it is displayed as a document instead of a book. This creates an inconvenience since now your books are in two locations instead of just one. Here is how to make your .mobi files be registered as books on the device.

The issue that is causing the device to register your .mobi file as a document rather than a book is that there was a personal doc tag (PDOC) placed in the .mobi file during conversion. This tag needs to be removed by reconverting the book without the problematic PDOC.

Open calibre, click preferences, second row down (conversion), click output options. in the list on the left select mobi output. delete anything in the "personal doc tag" and leave it empty. click apply then close prefernces and close and restart calibre. now when you send book to device, they should show up in the Books category on your kindle.

Drauku • 5 yr. ago • Edited 5 yr. ago
EDIT: I think I found a solution to this. When I was converting the book files to .mobi format, Calibre automatically added a '[PDOC]' tag, and this makes the Kindle organize those "doc" files differently (as personal documents). As soon as I removed that tag from the conversion process, no more lost books! I had to go back through my entire Calibre library and re-convert the .mobi files in order to remove the tag. If this still doesn't work, try adding the '[EBOK]' tag to the MOBI output convert dialogue.

Here's a good guide on how to remove the [PDOC] tag in Calibre: https://www.tech-recipes.com/rx/20147/kindle-fire-how-to-display-mobi-files-as-books-and-not-documents/

The above guide describes how to remove the tag on each conversion, if you want to remove the default behavior of adding [PDOC] every time you convert to .mobi, you need to remove the tag from the Convert settings for the .mobi format