Regex Tester

Test regular expressions in real-time with match highlighting and group extraction.

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About Regular Expressions

Regular expressions (regex) are patterns used to match, search, and extract text. They power input validation, log parsing, search-and-replace operations, and data extraction in every programming language. Mastering regex is essential for backend development, DevOps, and data engineering.

This tester highlights matches in real-time as you type, shows captured groups, and supports all JavaScript regex flags (global, case-insensitive, multiline, dotAll, unicode). Test patterns for email validation, URL parsing, log filtering, or CSV field extraction — all in your browser.