Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java, C#/.NET, Rust.

RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp).

A regular expression (shortened as regex or regexp), [1] sometimes referred to as a rational expression, [2][3] is a sequence of characters that specifies a match pattern in text. Usually such patterns are …

Mar 17, 2026 · Regular expression syntax cheat sheet This page provides an overall cheat sheet of all the capabilities of RegExp syntax by aggregating the content of the articles in the RegExp guide. If …

Regular Expressions Syntax Reference. Includes tables showing syntax, examples and matches.

Dec 22, 2025 · A regular expression (regex) is a sequence of characters that defines a search pattern. It is mainly used for pattern matching in strings, such as finding, replacing, or validating text. Regex is …

Comprehensive regex cheatsheet with syntax reference, character classes, quantifiers, anchors, and common patterns. Quick reference guide for regular expressions with examples and explanations.

Regular expressions are extremely useful in extracting information from text such as code, log files, spreadsheets, or even documents. And while there is a lot of theory behind formal languages, the …

Test and generate regular expressions in real-time. Free online regex tool for developers with syntax highlighting, pre-built examples, and instant match results.

May 22, 2026 · Welcome to Regular-Expressions.info The Premier website about Regular Expressions A regular expression (regex or regexp for short) is a special text string for describing a search …