Regex Tester

JavaScript flavour, evaluated live as you type. Matches are highlighted in the sample, and every capture group is listed underneath.

Pattern

/ Regular expression / Flags

g find every match, not just the first i ignore capitalisation m ^ and $ match each line s . also matches a newline u full Unicode y match only at lastIndex

Sample text

Text to test against

Replace with

Use $1, $<name>, $& as usual.

Highlighted

Enter a pattern and some sample text.

After replacing

Matches

Nothing yet.

Quick reference

. any character except newline

\d \w \s digit, word character, whitespace

\D \W \S the opposite of each

[abc] any one of a, b or c

[^abc] anything except those

a|b a or b

* zero or more

+ one or more

? zero or one

{2,5} between two and five

*? lazy, take as few as possible

(abc) capture group

(?:abc) group without capturing

(?<year>\d{4}) named group

^ $ start and end

\b word boundary

(?=abc) followed by

(?!abc) not followed by