Upgrading the Storage on your Kobo E-Reader

(Note: This worked on an old Kobo Clara HD, but will likely also work for any other Kobos with internal microSD cards for their OS and book storage.)

I picked up a gently used Kobo Clara and immediately set about looking online to see if there were any jailbreaks or fun things that could be done to it. Turns out people have been taking Kobos with microSD card storage and upgrading them for over a decade now, but I was not able to find a single cohesive guide for doing this on Linux or Unixlikes successfully, despite many claims otherwise.

Here’s what you’ll need:

• Any old Linux box, although I’m sure you can also do this on Mac OS and Windows, but that’s beyond the scope of this guide.
• Something to pry the plastic clips along the edges of your Kobo open (be gentle, go slow, you don’t want to break a clip by accident.)
• A larger microSD card than the included one, consider getting a higher class one as well (the stock ones are Class 4, I had a 64GB Class 1 card kicking around I used instead).
• a USB to microSD card reader or adapter, usually easily found in your junk drawer.

1. First we take out the old microSD card from the Kobo (carefully unplugging the internal battery prior to doing so, just in case).

2. Plug the microSD card into your Linux box, and create an image from the card. Before removing the microSD card, remount the FAT32 partition (/dev/sdb3 in my case) and copy it’s contents (including hidden folders like .kobo) to a folder on your machine.

To create a disk image, we’re going to use old reliable (dd):

sudo dd bs=4M if=/path/to/your/microSD/card of=/home/user/kobo_image.img

That should finish up after a few minutes.

4. Remove the Kobo’s original microSD card, plug in your new microSD card into your adapter.

5. Image the Kobo’s disk image that we created earlier onto the new microSD card. This will likely take a few minutes, which makes it a good time to get up and amble around a bit, maybe fix yourself a nice cup of coffee.

sudo dd bs=4M if=kobo_image.img of=/path/to/new/microSD/card

7. Once that’s done, the rest of the microSD card’s storage will NOT be available to the Kobo, since the imaging process does not automatically expand the storage area. To get that to happen, delete the FAT32 partition (the last one, labelled KOBOEREADER or similar) from the new microSD card you just imaged.

8. Once you’ve deleted the FAT32 partition, create a new one using gParted or KDE Partition Manager (or anything else you’d like, this was just the path of least resistance for me). Make sure that this new one takes up all of the remaining disk space on your new microSD card. It’s also important not to delete either of the two ext4 partitions that will be on the card while you are doing so.

9. Final step: Copy the files you saved from Step 2 onto the new FAT32 partition on your new microSD card. Literally just CTRL-A, CTRL-C, CTRL-V (into the new and mounted FAT32 partition we just made).

10. This isn’t really a step, but put the new card into the Kobo, re-attach the battery, and boot it up. If everything went as planned, you should be able to go to More > Settings > Device Information and see your Onboard Storage field reflect the new card’s additional storage.

And that’s that! I did this with an existing installation (that had book notes I didn’t want to lose) and everything worked correctly. I would recommend keeping that original disk image (kobo_image.img) around as a backup if your microSD card ever fails.