Regex Tester – Free Online Regular Expression Tester & Debugger Tool

The Regex Tester Tool is a free online regular expression testing and debugging tool that helps developers create, test, and validate regex patterns with instant feedback. Whether you’re working on data validation, search filters, or text extraction, this tool provides real-time regex matching results and highlights all captured groups visually.

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Regex Flags
Enter a regex pattern and test string to see highlighted matches
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Regex Tester FAQs

Frequently asked questions about using our Regex Tester tool.

A Regex Tester lets you write and test regular expression patterns to check how they match text data. It helps you find matches, extract text, or validate patterns efficiently.

Regex is used for pattern matching, data validation, text replacement, log filtering, and input sanitization in programming languages like JavaScript, Python, PHP, and Java.

Yes! It supports global (g), multiline (m), and case-insensitive (i) flags for more flexible matching.

Absolutely. The tool supports advanced regex syntax including groups, lookaheads, quantifiers, and special characters.

Yes — all regex testing happens locally in your browser. Nothing is uploaded or stored on any server.

Yes. It’s great for debugging regex patterns used in code for form validation, parsing text, or search filters.