This question, in it's raw form suggests that it is about information security - in this case, password. There are several ways to make the password more challenging to hack. It's either make it encrypted or make/own a key-gen or key generator.
Key generator - a key generator generates random characters which can be used as a password. It's effectivity lies on the number of characters used.
The answer for this question is none other than: Key-gen or key geneator.