Regex Tester

Test and debug regular expressions with real-time matching. Highlight matches and capture groups. Perfect for pattern testing and validation. Supports multiple regex flavors.

Regular Expression

Enter Regular Expression

Test String

Global (g)

Ignore Case (i)

Multiline (m)

Unicode (u)

Sticky (y)

Test Options

Replacement String (Optional)

Delimiter (Optional)

Test Results

Matches Found

Capture Groups

Pattern: -

Flags: -

Matches: 0

Groups: 0

Status: Ready

Quick Regex Patterns

Email Validation

[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}

Phone Number

^(\+\d{1,3}[- ]?)?\d{10}$

URL Validation

https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)

IP Address

^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$

Date (MM/DD/YYYY)

^(0[1-9]|1[0-2])\/(0[1-9]|[12][0-9]|3[01])\/\d{4}$

Hex Color

^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$

Username

^[a-zA-Z0-9_]{3,20}$

Strong Password

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d@$!%*?&]{8,}$

HTML Tags

<[^>]+>

Numbers Only

^\d+$

Letters Only

^[a-zA-Z]+$

Alphanumeric

^[a-zA-Z0-9]+$

About Regex Tester

Everything you need to know about regular expressions and how to use our tester effectively for pattern testing and validation

Understanding Regular Expressions

Regular expressions (regex) are powerful patterns used to match and manipulate text strings. They provide a concise and flexible way to search, replace, and validate text based on specific patterns. Regex is widely used in programming, text processing, data validation, and many other applications where pattern matching is required.

Regular expressions consist of a sequence of characters that define a search pattern. This pattern can include literal characters, metacharacters, character classes, quantifiers, and other special constructs that allow for complex pattern matching. Understanding regex syntax and the various components is essential for effective pattern creation and debugging.

Regex Components and Syntax

Regular expressions are composed of several key components that work together to create powerful search patterns. Literal characters match themselves, while metacharacters have special meanings and represent different types of pattern matching. Character classes allow you to match specific sets of characters, and quantifiers specify how many times a pattern should match.

Common regex components include anchors (^ for start, $ for end), character classes ([a-z] for lowercase letters), quantifiers (* for zero or more, + for one or more, ? for zero or one), and escape characters (\) for special characters. Understanding how these components interact is crucial for creating effective regex patterns and avoiding common pitfalls.

Testing and Debugging Regex

Testing and debugging regular expressions is an essential part of the development process. Regex patterns can be complex and sometimes behave unexpectedly, especially with edge cases and special characters. A good regex tester provides real-time feedback, highlighting matches and capture groups, and showing detailed information about pattern execution.

Our regex tester includes features like multiple regex flags (global, ignore case, multiline, etc.), capture group visualization, and detailed match information. This comprehensive testing environment helps developers understand how their regex patterns work, identify issues, and optimize performance. The ability to test against sample data and see immediate results makes regex development much more efficient.

Common Regex Patterns

There are many commonly used regex patterns that solve specific problems like email validation, phone number formatting, URL parsing, and data extraction. These patterns often serve as starting points for more complex regex development and can be customized to meet specific requirements.

Our quick regex patterns library includes frequently used patterns for email validation, phone numbers, URLs, IP addresses, dates, hex colors, usernames, passwords, HTML tags, and more. These patterns are tested and optimized for common use cases, making them valuable resources for developers who need to implement validation or parsing functionality quickly and reliably.

Real-time Testing

Test regex patterns instantly with real-time matching and result highlighting

Match Highlighting

Visualize matches and capture groups with color-coded highlighting

Multiple Flags

Support for various regex flags like global, ignore case, and multiline

Export Results

Download test results and regex patterns for documentation

Quick Patterns

Library of commonly used regex patterns for quick implementation

Pattern Explanation

Get detailed breakdowns of complex regex patterns to understand how they work