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

Menu RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp). Supports JavaScript & PHP/PCRE RegEx. Results update in real-time as you type. Roll over a match or …

The phrase regular expressions, or regexes, is often used to mean the specific, standard textual syntax for representing patterns for matching text, as distinct from the mathematical notation described below.

Dec 8, 2025 · 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 you need more information on a …

If you are a complete beginner, you should get a firm grasp of basic regex syntax just by reading the examples in the tables. I tried to introduce features in a logical order and to keep out oddities that I've …

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 …

A RegEx, or Regular Expression, is a sequence of characters that forms a search pattern. RegEx can be used to check if a string contains the specified search pattern.

Oct 29, 2025 · This tutorial teaches you how to create your own regular expressions, starting with the most basic regex concepts and ending with the most advanced and specialized capabilities.

Regex is short for Regular Expression. It helps to match, find or manage text. Start by typing OK in the Regex field to proceed to the first step and access the more detailed description.. Understand? OK …

And while there is a lot of theory behind formal languages, the following lessons and examples will explore the more practical uses of regular expressions so that you can use them as quickly as possible.