Online Regex Tester for PHP, PCRE, Python, Golang and JavaScript

In plain words

Regular Expressions 101 is an online regex tester and debugger supporting multiple programming languages including PCRE2, JavaScript, Python, Go, Java, .NET, Rust, and POSIX variants. It features real-time match highlighting, detailed explanations of regex patterns, substitution testing, unit tests, benchmarking capabilities, and code generation. Developers use it to test, debug, and understand regular expressions across different platforms.

written from the facts on this page · September 2026

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  Online tool to learn, build, & test Regular Expressions

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• RF
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