Test regular expressions with live highlighting and replace.
Matches
Enter a pattern and some text to see matches highlighted.
Last reviewed by the OnlineToolPro team
Write a regular expression and see every match highlighted as you type, with capture groups listed. Try a replacement to see the result. Uses the JavaScript regex engine built into your browser.
How it works
3 simple steps. No experience needed.
Good to know
g finds every match instead of only the first, i ignores letter case, m makes ^ and $ match at the start and end of each line, s lets . match line breaks, and u enables full Unicode support.
In the replacement field, $1, $2 and so on insert capture groups, and $& inserts the whole match. For example, replacing (\w+)@(\w+) with $2 at $1 swaps the parts around the @.
FAQ
JavaScript (ECMAScript). Most patterns work the same in other languages, but some features differ.
Most everyday patterns work the same. Differences appear with lookbehinds, named groups syntax and some flags, so test in your target language too.
Patterns like a* can match zero characters. Use + instead of * if at least one character is required.
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