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Regex Tester & Builder
Test regular expressions with real-time matching, pattern explanations, and code generation. Build and debug regex patterns with visual feedback.
Last updated: 1/21/2025
Regex Tester & Builder
Regular Expression
Test String
Highlighted Matches
Match Details
Frequently Asked Questions
What is a regular expression (regex)?
A regular expression is a sequence of characters that defines a search pattern. It's used for pattern matching within strings, allowing you to search, match, and manipulate text based on specific rules and patterns.
How do I test my regex pattern?
Enter your regex pattern in the expression field, add your test string in the test area, and see real-time results. Matches are highlighted in yellow, and detailed match information is shown in the results panel.
What do the regex flags mean?
Flags modify how the regex behaves: 'g' finds all matches, 'i' ignores case, 'm' treats ^ and $ as line boundaries, 's' makes . match newlines, 'u' enables unicode, and 'y' matches from the current position.
Can I generate code for different programming languages?
Yes! The Code Generator tab provides ready-to-use code snippets for JavaScript, Python, and PHP. The generated code includes your pattern, flags, and test string.
What are the common regex patterns for?
The Pattern Library contains tested regex patterns for common validation tasks like emails, phone numbers, URLs, IP addresses, passwords, and more. These patterns are production-ready and well-documented.
How do I understand what my regex pattern does?
The tool provides pattern breakdown explanations that describe what each part of your regex does. Hover over highlighted sections to see detailed explanations of character classes, quantifiers, and anchors.
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