Regex Tester, Matcher & Diagram
Runs 100% in your browser — your files never leave your device.
Regular expressions are easier to debug when matches, capture ranges, and structure are visible together. Enter a JavaScript pattern, flags, and test text to inspect every match and group, generate sample matching text, or load an SVG railroad-style diagram only when requested.
How it works
- 1
Enter a pattern and flags
- 2
Paste test text and inspect matches
- 3
Generate an example or render the diagram
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