Updated about 9 yrs, 2 mths ago (August 23, 2015). Know a better answer? Let me know!
Kindle Root Password Generator
Amazon’s Kindle uses a root password derived from the serial number. This tool will help you calculate your Kindle’s root password.
Calculate Root Password
To calculate your Kindle’s root password, first find your Kindle’s serial number. This can be found from the Settings page.
Then, enter your serial number below, and the page will (hopefully) calculate your root password.
Enter your Kindle’s serial number here:
Note that this page uses client-side JavaScript, so the serial number is never sent to the server–just in case you were paranoid and wanted to keep your serial number secret for some reason.
Possible root passwords
There are a few possible root passwords, depending on the model of your Kindle. Try them until one works, or if none work, let me know.