Regex Tester

Test and debug regular expressions in real-time. Supports JavaScript RegExp flags and syntax.

//g
Test String
34 characters1 lines
Match Preview
7 matches
Hello world! This is a regex test.
Matches foundReadOnly

Online Regex Tester - Real-time Evaluation

Test regular expressions in real-time with highlighting. Supports all JavaScript RegExp flags. Free developer tool.

Key Features

Real-time regex testing
Syntax highlighting
Support for g, i, m, s, u, y flags
Instant match count
100% Client-side privacy

100% Private & Secure

All processing happens directly in your browser. Your data never leaves your device — we don't upload, store, or have access to any of your content.

Instant & Offline-Ready

No server roundtrips means instant results. Once this page is loaded, the tool works even without an internet connection.