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Regex Tester

Test JavaScript regular expressions with live match highlighting.

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Runs locally in your browser. Your files are never uploaded.

About this tool

Write a regular expression and see matches, capture groups and named groups highlighted live, and test replacements. Includes a quick cheat sheet.

How to use it

  1. Type a pattern and flags.
  2. Paste test text.
  3. Inspect matches and groups.
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