Online regex tester with support for g/i/m/s flags. Real-time match highlighting. Runs locally in your browser for fast regex debugging.
TL;DR: Free online regex tester with support for g/i/m/s flags. Real-time match highlighting for fast debugging. Runs entirely locally in your browser, no registration required.
This tool runs entirely in your browser. Open DevTools → Network panel and search your input — it appears in no request.
FAQ
Completely free, no registration needed. Test regular expressions in real-time in your browser — all matching runs locally with no usage limits.
It supports common flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (Unicode), and y (sticky). You can combine them freely.
No. All regex matching and testing runs locally in your browser. Your text and regex patterns are never uploaded to any server.
Yes. The tool displays all matches in real-time with highlighting, making it easy to debug regex patterns and quickly locate match positions.
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