Test a regular expression live
Type a pattern and flags (g all matches, i ignore case, m multiline, s dot matches newline) and see every match highlighted in the text with its capture groups and position. The engine is JavaScript's own, so results match what you get in Node, browsers, Google Sheets' REGEXMATCH and most editors.
Cheat sheet
\d \w \s | digit, word character, whitespace (capitals negate) |
. ^ $ | any character, start, end |
* + ? {n,m} | 0+, 1+, 0–1, between n and m |
[abc] [^abc] [a-z] | sets and ranges |
(x) (?:x) (?<name>x) | capture, non-capture, named group |
a|b \b | alternation, word boundary |
(?=x) (?!x) | lookahead, negative lookahead |