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Regular Expression Tester

Test and debug regular expressions with real-time pattern matching, group capture analysis, and comprehensive pattern explanations. Supports all JavaScript regex features and flags.

Input

Input

Output

Output will appear here

How It Works

Privacy First

This regular expression tester processes your data entirely in your browser. No data is uploaded to any server, ensuring complete privacy and security.

Lightning Fast

Instant processing with real-time validation and error detection. No waiting, no delays - just immediate results.

Versatile Use Cases

  • Form validation and input sanitization
  • Data extraction from text files
  • Search and replace operations

Mobile Friendly

Responsive design that works perfectly on all devices and screen sizes. Touch-friendly interface for mobile users.

Frequently Asked Questions

What regex flags are supported?
All JavaScript regex flags: global (g), ignore case (i), multiline (m), dotAll (s), unicode (u), and sticky (y). Each flag can be toggled individually.
How do I test against multiple inputs?
Enable "Test Multiple Inputs" and enter each test string on a separate line. The tool will test your pattern against all inputs and show results for each.
Can I see capture groups?
Yes! Enable "Show Groups" to see both numbered capture groups and named groups. The tool displays the content of each group for every match.
What test modes are available?
Four modes: Test (boolean match), Match (find matches), Replace (substitute text), and Split (divide text). Each mode provides different output and functionality.
How does pattern explanation work?
The tool analyzes your regex pattern and explains common components like anchors, quantifiers, character classes, and other regex elements.

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