Which flags are supported?

Any JavaScript RegExp flags your browser supports, such as g, i, m, s, and u.

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Regex Tester

Test regular expressions with live matches.

Write a pattern, set flags, and see matches update as you type.

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Test JavaScript regular expressions live, inspect capture groups, and preview replacements.

Pattern

//g

Matches

Flags

Test text

Highlighted matches

Contact hello@weakless.pro or sales@weakless.pro. Billing questions go to invoices@weakless.pro.

Match list

#1index 8hello@weakless.pro$1=hello $2=weakless.pro

#2index 30sales@weakless.pro$1=sales $2=weakless.pro

#3index 74invoices@weakless.pro$1=invoices $2=weakless.pro

Replace mode

Regex cheat sheet

.: Any character except newline (any char with s)
\d \D: Digit / non-digit
\w \W: Word character / non-word character
\s \S: Whitespace / non-whitespace
\b \B: Word boundary / non-boundary
^ $: Start / end of input (or line with m)
[abc] [^abc]: Character set / negated set
[a-z0-9]: Character range
a|b: Alternation — a or b
* + ?: Zero or more / one or more / optional
*? +?: Lazy quantifiers (match as little as possible)
{2} {2,} {2,5}: Exactly / at least / between n and m
(abc): Capture group
(?:abc): Non-capturing group
(?<name>abc): Named capture group
(?=abc) (?!abc): Lookahead / negative lookahead
(?<=abc) (?<!abc): Lookbehind / negative lookbehind
$1 $<name> $&: Replacement references: group, named group, whole match

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Frequently asked questions

Which flags are supported?: Any JavaScript RegExp flags your browser supports, such as g, i, m, s, and u.

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