Regex Tester: Validate & Debug Your Regular Expressions

Our Regex Tester Tool basically simplifies the process of working with regular expressions. Input your regex pattern and test string, and watch as the tool highlights matches instantly. Whether you're debugging complex patterns or learning the basics, our Regex Tester Tool is designed to make your regex experience smooth and efficient.

A regular expression (regex or regexp for short) is a special text string for describing a search pattern. You can think of regular expressions as wildcards on steroids. You are probably familiar with wildcard notations such as *.txt to find all text files in a file manager. The regex equivalent is .*\.txt$.

Regular expressions are widely used in programming languages, text editors, and command-line tools to search and manipulate text. You can use regular expressions to validate input, search for patterns in text, and extract text from strings. They are a powerful tool for working with text data and can save you a lot of time and effort when working with complex patterns.

Regular expressions are a powerful tool for matching various patterns in text. Here are some of the basic rules:

1. Anchors

^ and $ are used to match the start and end of a line, respectively.

2. Quantifiers

* means zero or more, + means one or more, and ? means zero or one.

3. Character classes

[abc] matches a or b or c, [a-z] matches any letter from a to z, and [^0-9] matches anything except a digit.

4. Grouping and capturing

( ) is used to group and capture matched text.

5. Alternation

| is used to match either a or b.

6. Escaping

\ is used to escape special characters like ., *, and +.

The tool works via Javascript so it supports JavaScript regular expressions. JavaScript regular expressions are a subset of the Perl regular expressions. The tool supports all the JavaScript regular expression syntax and flags. You can also use the tool to test your regular expressions for JavaScript, PHP, Python, Ruby, Java, and other programming languages.