Regex Tester
Test and debug regular expressions with live matching and highlights
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What is Regex Tester?
Free online regex tester to test regular expressions against sample text with real-time match highlighting.
Enter your regex pattern and flags, then see all matches highlighted instantly in your test string. The tool shows detailed match information including capture groups, indices, and match count. Perfect for building and debugging regex patterns for JavaScript, Python, or any language that supports standard regex syntax. No signup required.
How to Use Regex Tester
- 1Enter your regular expression pattern in the pattern field
- 2Select the flags you need: global (g), case-insensitive (i), multiline (m), dotAll (s)
- 3Type or paste your test string in the text area below
- 4See matches highlighted in real time with detailed match information
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