Regex Tester & Debugger
Test JavaScript regular expressions against sample text with live highlighting, flag toggles and a capture-group table. Fast, private and offline-ready.
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See matches as you type
Enter a pattern and it is applied live to your test string, highlighting every match in place. Toggle the g, i, m, s, u and y flags with checkboxes and watch the results update instantly.
Inspect capture groups
A results table lists each match, its position in the text, and the contents of every capture group — invaluable for debugging complex extraction patterns before you ship them.
JavaScript-accurate and safe
Patterns use the native RegExp engine, so behaviour matches exactly what your JavaScript or TypeScript code will do. Input length is capped and iteration is guarded to prevent a pathological pattern from freezing the page.
How to regex tester
- Type your regular expression pattern.
- Toggle the flags you need (global, ignore case, etc.).
- Paste sample text to test against.
- Review highlighted matches and the capture-group table.