Regex Tester

Write and debug regular expressions in real-time with capture group inspection.

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Enter a valid regex and test string above...

How to Use Regex Tester

  1. Enter your regular expression pattern in the regex input field.
  2. Toggle regex flags (Global 'g', Case Insensitive 'i', Multiline 'm', DotAll 's').
  3. Type or paste your test text in the test string area.
  4. Inspect matched substrings, capture groups, and match counts in the live results panel.

Key Features & Privacy Guarantee

  • Live Highlighting: Matched characters and groups are highlighted in real-time.
  • Capture Group Inspector: Detailed breakdown of each match index and capture groups.
  • Common Pattern Library: Pre-built quick regex snippets for emails, URLs, dates, and phone numbers.

Frequently Asked Questions

Which Regex engine is used?

The tester uses JavaScript's ECMAScript Regular Expression engine running client-side.