rgxg - rgxg source code. Contribute to rgxg/rgxg development by creating an account on GitHub.
RegexMagic - Use RegexMagic to generate complete regular expressions to your specifications by using RegexMagic's flexible patterns, instead of the cryptic regex syntax.
RegexBuddy - RegexBuddy is your perfect companion for working with regular expressions.
regular expressions 101 - Extensive regex tester and debugger with highlighting for PHP, PCRE, Python and JavaScript.
i Hate Regex - regex cheatsheet for the haters
RegExr - RegExr.com is an online tool to learn, build, and test Regular Expressions.