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Regex Tester
Type a JavaScript regular expression, flags and test text — matches are highlighted live with their character spans, capture groups and named groups listed. The exported report records every span so results are reproducible.
A little guidance. A better result.
How to use Regex Tester
JavaScript regex + flags + text → live-highlighted matches with spans, capture groups and named groups; exportable report.
Prepare your input
Enter a JavaScript regex, flags and test text.
Use the workspace
Inspect highlighted matches, spans and capture groups.
Check your result
Test both matching and non-matching cases before exporting the report.
Know the limits
Regex dialects differ. Complex patterns on long text can be expensive; start with short samples.
Where does my input go?
This browser tool processes your input on your device. Optional analytics is a separate choice; it is not needed to use the tool. Keep your original until you have checked the result.
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