Warning: Beta version
This is a simple apps to salt keyword.
I have always the same problem, I have some strong passwords for the important websites (mail, banks, etc...). But it's very annoying for junk sites to remember unique passwords. Often we create a password for the websites and we don't use it for several months. This is a generator of unique password for junk sites. You have only to remember a unique password.
Warning: just use it for website with no critical informations.
The formula to make this transformation is:
Trunk(SHA-512-B64(password + ':' + ctx_identifier), length) = unique password
The hash library is jsSHA.