Regex Tester
Write a regular expression and test it against sample text, with matches highlighted live — entirely in your browser, using JavaScript's native regex engine.
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Frequently Asked Questions
Which regex flavor does this use?
JavaScript's native RegExp engine — the same syntax used in browsers and Node.js. Most patterns are compatible with PCRE/Python's re, with some differences in lookbehind and Unicode property support depending on flags.
What do the common flags mean?
g = global (find all matches, not just the first), i = case-insensitive, m = multiline (^ and $ match line boundaries), s = dotAll (. matches newlines too).
Is my text sent anywhere?
No — matching runs entirely in your browser's JavaScript engine. Nothing you type is ever transmitted.
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