Living in a small London flat, I’ve developed a strong aversion to physical clutter. As such, I’m very fond of e-books. And, like the majority of lazy people, I tend to buy most (although not all) of them from Amazon. And here we run into a problem: Amazon is, if not evil, certainly not on our side. They’ve taken books from accounts before, and no doubt will again. As such, I consider it healthy to maintain backups.

This turns out to be fairly easy to do, thanks to Calibre. This is an open source e-book manager, and on top of being a great way to track your various e-books is the ability to strip Amazon’s DRM.

To do this:

  • Install the Kindle application for Mac.
  • Open it, then log in using your Amazon account.
  • Download the books you wish to back up.
  • They’ll be placed in ~/Library/Containers/ Support/Kindle/My Kindle/Content.

While it’s easy enough to copy everything on the first download, I tend to find all files modified in the last hour so to only backup my new downloads.

cd ~/Library/Containers/\ Support/Kindle/My\ Kindle\ Content
find . -cmin -60 -name '*.az*' -exec cp \{\} ~/Desktop \;

This will copy the most recent files to your desktop.

Now, open Calibre, and drag the azw files from your dekstop into the Calibre window. They’ll be imported, and cleaned of DRM during the process.

As a final touch, if you move the Calibre library directory to the cloud provider of your choice (e.g. iCloud, Dropbox) you end up with a cloud backup, and can then access these e-books on all your computers.