- Great match and replace tester.
- Haven't used this one much but it looks nice.
- This resource has online RegEx testers for many languages
- I personally never use this site, but it has an interesting way of visualizing the matching so it may be helpful in learning
- A good .Net tester. Actually uses the .Net regex library so you're pretty much assured compatibility with .Net's regex libs.
- This is a simple regex tester, nice for quickly testing a regex against some data.
- This is an awesome website. You can type out a regular expression, give it seed data, and then share that exact scenario with someone so they can either learn from what you did, or help you debug your expression. Really useful if you need to send a regex with some seed data to someone to ask for help or explain something. You can also do, "unit tests" of sorts where you can give it things that should not match, and things that should, and it will tell you if your regex "passes" your "tests".
- This is a Ruby regular expression editor
- This is a book that I have not personally read, but is probably a really good reference resource for regular expressions in general.
- Python regular expression tester