DevKitLabDeveloper utilities

Regex Tester

Test and debug JavaScript regular expressions with real-time match highlighting.

100% Client-Side Browser Execution

What is Regex Tester?

Test regular expression patterns against sample text. View matched groups, match index positions, flags (g, i, m, s, u), and real-time execution outputs.

Key Features & Capabilities

Real-time match highlighting
Capture group breakdown
Regex flag toggles (g, i, m, s)

How to Use Regex Tester

  1. 1Enter your regex pattern and flags (e.g. /\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b/gi).
  2. 2Paste your test text string.
  3. 3Review highlight matches and capture group extractions.
Data Privacy & Security Guarantee

When you use Regex Tester, all input processing is executed completely inside your Web browser memory via client-side JavaScript. Your text and files are never stored, logged, or sent to backend databases.

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Frequently Asked Questions

Which regex syntax is supported?

The tester uses standard ECMAScript / JavaScript regular expression syntax native to modern browsers.