Regex Tester SECURE

Test regular expressions with real-time match highlighting and flag support.

Test and debug regular expressions instantly. Supports global, case-insensitive, multiline, and other flags.

How to use this tool
  • Enter your regex pattern between the slashes (e.g., \d+)
  • Add flags like g, i, m in the flags field
  • Enter test string in the input area
  • Matches are highlighted in real-time
  • View match count and match details
Privacy & Safety

All processing is done locally in your browser. No data is uploaded or stored.

Why choose this tool?

Real-time highlighting, flag support, match history, and pattern testing.

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Live Mode
Test String
Regex Matches

Regex History

No history yet. Test a regex to see it here.

Quick Reference

\d - Digit (0-9)
\w - Word character
\s - Whitespace
. - Any character
* - 0 or more
+ - 1 or more
? - 0 or 1
{n} - Exactly n times
[abc] - a or b or c
(abc) - Capture group
What flags are supported?

g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), y (sticky)

How do I use this tool?

Enter your pattern between slashes, add flags, and type your test string. Matches will be highlighted instantly.

Is this tool free?

Yes – completely free, no registration required.