OmniToolsFree

Regex tester

Test a JavaScript regular expression, with flags, match text and groups. A long run is stopped.

  • 5 MB of text
  • The test is stopped after about a second
  • 200 matches are shown
  • Runs in the browser

This runs in your browser. What you type is not uploaded by this tool.

JavaScript regular expressions for Regex tester. A run that takes too long is stopped.

    How to use it

    Three steps

    1. 01

      Enter a JavaScript pattern and flags.

    2. 02

      Paste the text to test.

    3. 03

      Run it. Groups are listed under each match.

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    Questions

    Which flavor is this?

    JavaScript, as implemented by this browser. It is not PCRE or Python.

    What if the pattern is catastrophic?

    The test runs in a Web Worker and is terminated if it takes too long, so the page can stay usable.