Debuggex might be a bit more popular than RegexPal. We know about 4 links to it since March 2021 and only 3 links to RegexPal. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
BUT - As far as resources for building out the regex patterns, I use regexpal.com and a copy of this https://cheatography.com/davechild/cheat-sheets/regular-expressions/pdf/ printed out beside me. Once you get into it, the power of subgroups, and lookahead/behind processing beats some of the mental gymnastics you would need to go to code it out in your language of choice. Source: almost 3 years ago
Spend an afternoon really diving into it, bookmark regexpal.com, and call it a day IMO. Source: almost 3 years ago
i’m a professional developer and I just relearn it every time I need it, which is about once or twice a year, but depending on someone’s specialty they may swim around in it all day. It can get really complicated. https://regexpal.com is where I kick it around testing until it works. Source: almost 3 years ago
Debuggex.com is a great tool for visualizing how a regex will execute character-by-character and testing it against a variety of inputs. Source: over 2 years ago
Combine that with Debuggex and you're a god at the game )). Source: about 3 years ago
My trick with understanding regexes, is not actually trying to understand them by looking at the text form. Instead copy paste them in a visualliser, like debuggex.com. This makes them sooo much easier to understand. Once you do that with this one (and also read the PR description), you'll realize it actually isn't that crazy complex. Source: over 3 years ago
Debuggex.com is also great, as you get a graphical preview of what the regex is actually doing. Source: over 3 years ago
regular expressions 101 - Extensive regex tester and debugger with highlighting for PHP, PCRE, Python and JavaScript.
RegExr - RegExr.com is an online tool to learn, build, and test Regular Expressions.
i Hate Regex - regex cheatsheet for the haters
Expresso - The award-winning Expresso editor is equally suitable as a teaching tool for the beginning user of regular expressions or as a full-featured development environment for the experienced programmer with an extensive knowledge of regular expressions.
rubular - A ruby based regular expression editor
Regex Hero - Online Silverlight regular expression tester with instantaneous highlighting, C# and VB.NET code generation, code completion, regex analysis, benchmarking, and more.