They change it frequently enough, that whenever I need to find it, it's listed under a different name and I have no idea where to look.
Amazon gives free unlimited backup account with prime (which is around $99)
I checked on this because I it sounded too good. Here's what I found.
Your Amazon Prime membership comes with Amazon Prime Photos, unlimited photo storage and 5 GB for videos, music, and other files.
Unlimited backup of any files is $60 a year.
After a number of decimal places, nobody gives a damn.