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Regex Debugger
Test a regex against sample text and see each match with its index position and any named/numbered capture groups.
How to Use Regex Debugger
- 1Enter your regex pattern
- 2Add a line with ---, then your test text
- 3Click Process
- 4Review each match's index and captured groups
Frequently Asked Questions
The Regex Tester only lists matched text; this Debugger additionally shows each match's index position in the string and any capture group values (named or numbered), which is more useful when refining a pattern.
Your regex pattern, then a line with just ---, then the text to test it against.
Yes — if your pattern uses (?<name>...) named groups, their captured values are shown alongside the match.
No — matching happens entirely in your browser using the real JavaScript regex engine.
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View a reference sheet of common regex patterns and syntax basics — the same static content as the Regex Generator tool.