Regex Tester

Test regular expressions against sample strings with real-time match highlighting.

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Regex Tester

Test regular expressions against sample strings with real-time match highlighting.

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0 matches

How it works

  1. 1
    Enter a regex patternType your regular expression without delimiters - just the pattern.
  2. 2
    Set flagsCommon flags: g (global), i (case-insensitive), m (multiline).
  3. 3
    See matchesMatches are highlighted in the test string in real-time.

Frequently asked questions

What are regex flags?
Flags modify matching behavior: g (find all matches), i (ignore case), m (^ and $ match line boundaries), s (dot matches newlines).
Why is my regex not matching?
Check the error message - it usually points to the exact issue. Common problems: unescaped special characters, unclosed groups, or invalid quantifiers.
Can I use this for data validation?
Yes. Test your validation regex against sample inputs to see exactly what it matches and misses before using it in code.

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