Regex Tester & Debugger - Test, Validate & Highlight Pattern | ToolsAid
Professional Regular Expression Tester. Validate patterns, highlight matches in real-time, and debug complex Regex logic online. JavaScript flavor supported.
Matches will appear highlighted here...
key Features
- Real-time Regex Testing & Highlighting
- Detailed Match Information
- Support for Global, Case Insensitive, and Multiline flags
- Built-in Quick Reference for common patterns
- 100% Client-Side Processing
The Regex Tester allows you to write, debug, and optimize Regular Expressions directly in your browser. RegEx is powerful but can be confusing—our tool provides immediate visual feedback to make it easier.
Real-time Feedback: As you type your pattern, we instantly highlight matches in your test string. This rapid loop helps you catch edge cases and refine your logic quickly.
Privacy First: Your test strings and patterns never leave your browser. Feel free to test distinct data without worrying about it being sent to a server.
Frequently Asked Questions
Which Regex flavor is supported?
This tool uses JavaScript's built-in RegExp engine. It supports standard JavaScript regex syntax.
Why are my results different from python/pcre?
Different languages have slightly different Regex implementations. This tool specifically tests for JavaScript environments (Node.js, Browsers).
Can I use flags like Global or Case Insensitive?
Yes, common flags like 'g' (global), 'i' (case insensitive), and 'm' (multiline) are fully supported.
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