Regex Tester & Matcher

What is a Regular Expression?

A Regular Expression (Regex) is a powerful pattern-matching language used to search, validate, and manipulate text. It is one of the most essential tools in a developer's toolkit for tasks ranging from input validation to complex data extraction.

How to Use This Regex Tester

The tester provides a real-time environment powered by JavaScript's native RegExp engine:

• Enter your pattern in the top field (without slashes)
• Choose flags (g for global, i for case-insensitive, m for multiline, etc.)
• Paste your test text below — matches highlight instantly
• View detailed capture groups and match information on the right

Common Use Cases

• Validating emails, phone numbers, URLs, and passwords
• Extracting specific data from logs or large text files
• Performing bulk find-and-replace operations with complex rules
• Parsing structured data (CSV, logs, API responses)
• Testing and debugging regex before using it in production code

Complete Privacy

All regex evaluation happens 100% in your browser. Your test strings and patterns are never sent to any server — ideal for working with sensitive data or proprietary patterns.

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