Regex101 is basically my "regex editor", to the point that I have a keybinding in my normal code editor that opens it in the browser for me.

It's such a good resource for understanding and writing both simple and complicated regex.

I want to call out https://www.regular-expressions.info/ since it was, for a long time, one of the better/best resources on regexes that I was able to find. I learned a lot from this ... guy, essentially.

This website is great and well worth a donation if you've benefited from it in the past.

As a "next level" site, also give https://rexegg.com a look.

regex101 and similar sites like [1] are great

but, I always try to add a warning when recommending - should use them only for the flavors supported (PCRE, Python, etc) I've seen many using it for cli tools and wonder why things like non-greedy or lookarounds don't work.

[1] https://www.debuggex.com/

Why not use sublime as your regex editor? What makes regex101 special?

Can't speak for Sublime but 101 has inline highlighting and explanations per regex feature/flag/pattern. It really is awesome.

It's like the difference between writing C++ in Nano and writing C++ in Visual Studio.