Regex101 - free regular expression tool

Published  Jan 05, 2013
Updated  Jan 05, 2013
0  3


So this is my most recent project. Regular expression website where you build your expressions and they get highlighted and explained on the fly. You also get elaborate information on what your expression matches. Pretty much everything you want when you deal with regular expressions.

The site also features a regex quiz which is there for educational purposes. It is meant to help you explore the power of regular expressions and improve on your skills.

I hope you like it :)


Sign in to comment.
Lindrian   -  Jan 13, 2013

Bunch of new stuff on the site:


  • Improved my code across the board tremendously. Should result in much better performance (even though it might not be noticeable). Also made my HTML a tiny bit more valid.
  • Improved compability for Internet Explorer -- even though it is still lacking more than I'd want it to.
  • New quick reference
  • Improved the highlightning
  • Improved the explanation for regexes
  • Patched up tons of tasks and added more robust tests.
  • Added two new tasks to the quiz (more coming!!!)
  • Added ratings to the quiz so you can compete with everyone else playing!
  • Improved tooltips performance (this was really bad in larger test samples)
  • Added a substitution box (remember /g affects replacements too!)
  • Added a community where you can share regular expressions!

I think these are all the changes that you'll actually notice, even though I have done a lot more work behind the scenes.

I hope you enjoy the changes! All form of feedback is awesome!

Hawkee  -  Jan 13, 2013

I like the community feature, that's pretty neat. You should emphasize the search as that could be incredibly useful as your database of regular expressions grows.

Sign in to comment

sean   -  Jan 10, 2013

Impressive tool. Will certainly bookmark this for future reference :)

Lindrian  -  Jan 10, 2013


sean  -  Jan 11, 2013

Is this open source? It would be handy to host this on internal networks :)

Lindrian  -  Jan 11, 2013

No sorry, it is currently not open source. You are however free to use this service wherever you like really.

Sign in to comment

Hawkee   -  Jan 05, 2013

@Lindrian Great to see you back! The tool looks quite useful. I'll give it a try the next time I need to build a regular expression.

Lindrian  -  Jan 05, 2013

Thanks for the kind words old friend :). I hope it will aid you in your future regex-endeavours!

Hawkee  -  Jan 05, 2013

Have you built any other apps?

Lindrian  -  Jan 05, 2013

Yeah I have built a few but they were commercial and are privately hosted by the company that bought it, so it's nothing I can show off. This is my only own project I have right now :). How about you, anything besides you want to show me ;)?

Hawkee  -  Jan 05, 2013

That's why it's so important to develop tools independently. Otherwise you've got no control over who uses them. I don't have anything else worth mentioning. This site is my development playground.

Sign in to comment

Are you sure you want to unfollow this person?
Are you sure you want to delete this?
Click "Unsubscribe" to stop receiving notices pertaining to this post.
Click "Subscribe" to resume notices pertaining to this post.