I were questioned many times about how to make a simple and secure password programmatically!
I ended up building a convenient app where you can pass in the site youre using, and the email/username associated with that site, say your login ID. This would salt and hash those answers creating you a 15 character password thats COMPLETELY random. But for you all you need to remember is the email you used on the site.
This app is 100% clean and require no internet connection to work. Guarantee no password stolen in the using of this app :)