A simple npm package that checks the password strength of a certain passphrase. A password strength checker based from Javascript RegEx. This repository contains regular expression (regex) patterns ...

The regex library of matching characters has been growing in Javascript for a while. The Mozilla MDN for RegExp has a breakdown of what is supported, which may be well beyond what most people expect.

It's been a while since I worked on regexs in JavaScript, but generally the way you do this in most programming languages is to build the regex as a string and then pass it into the regex engine.