what it does
no more guessing what (?:[^\s]+) means.
four jobs. all token-by-token. all in your terminal. no api call, no internet round-trip, no “ai might hallucinate” surprise — just a plain parser that explains every glyph.
break down a pattern
$ regexlab '^\d{3}-\d{4}$'
^ → start of line
\d{3} → digit, exactly 3 times
- → literal "-"
\d{4} → digit, exactly 4 times
$ → end of line
\d{3} → digit, exactly 3 times
- → literal "-"
\d{4} → digit, exactly 4 times
$ → end of line
annotate inline
$ regexlab --inline '\bfoo\b'
\b word boundary
foo literal "foo"
\b word boundary
foo literal "foo"
\b word boundary
diff two patterns
$ regexlab diff 'a+' 'a*'
a+ → one-or-more "a"
a* → zero-or-more "a"
diff: + accepts >=1, * accepts >=0
a* → zero-or-more "a"
diff: + accepts >=1, * accepts >=0
test against samples
$ regexlab test '^\d+$' 42 4.2 abc
42 → match
4.2 → no match
abc → no match
4.2 → no match
abc → no match
install
three ways. all painless.
npm
$ npm i -g @v0idd0/regexlab
node 14+ on linux / macos / windows. updates with npm update -g.
github releases
$ curl -L github.com/voidd0/regexlab/releases/latest
single static binary. zero runtime needed. all releases →
git clone
$ git clone github.com/voidd0/regexlab
read the source, send a pr, fork it. mit licence, no cla. repo →
why we built it
we kept pasting our own regexes back into regex101 just to remember what they did. so we wrote a parser that explains them in english — offline, in the terminal, in 0.04 seconds.
no telemetry. no signup. no “upgrade for the pro explanation.” mit forever, even if vøiddo dies tomorrow — the source is public and the npm package is yours to fork.