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Regular Expression Tester Online

Test JavaScript regular expressions with live highlighting, match counts, capture groups, flag toggles, and built-in pattern presets. Matching runs locally in your browser.

Quick switch→Regex Replacer
RegexTestingDeveloper
Quick switch:Regex ReplacerRegex ExtractorRegex Explainer

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Use cases

  • Validate a pattern before shipping code
  • Debug log extraction or parsing rules
  • Check form-validation edge cases

How to use

  1. Enter a pattern and toggle flags as needed
  2. Paste the text to test
  3. Review highlights, match count, and capture-group details

Example input and output

Input

Pattern: \b[a-z]+\b
Text: hello 123 world

Output

hello, world

FAQ

Which flags are supported?

Common JavaScript flags such as g, i, m, and s can be toggled from the UI.

Can I inspect capture groups?

Yes. Numbered and named capture groups for each match are listed in the match details panel.

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