Regex Tester & Explainer

Test and validate regex expressions online with real-time match highlighting and syntax explanation.

What is Regular Expression?

A Regular Expression (Regex) is a pattern used to match combinations of characters in text. It’s widely used in text processing, data validation, search and replace operations.

How to Use This Tool?

  1. Select Preset: Click preset buttons (like “Email”, “Phone”) to quickly load common patterns.
  2. Enter Pattern: Type or modify your regex pattern in the input field.
  3. Enter Test Text: Input the text you want to test in the text area below.
  4. View Results: See real-time match highlighting and group details.

Common Regex Patterns

Scenario Pattern Description
Email [a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,} Match email addresses
Phone \d{3,4}-?\d{7,8} Match domestic phone numbers
URL https?://[^\s]+ Match web links
Date \d{4}-\d{2}-\d{2} Match YYYY-MM-DD format
Color #[0-9A-Fa-f]{6} Match hex color codes
IP Address \b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b Match IPv4 addresses

FAQ

Is this tool secure?

Absolutely secure. This tool runs entirely in your browser; no data is uploaded to any server.

What regex syntax is supported?

This tool supports JavaScript regex syntax, including:

  • Character classes: [abc], [^abc], \d, \w, \s
  • Quantifiers: *, +, ?, {n}, {n,}, {n,m}
  • Anchors: ^, $, \b
  • Groups: (...), (?:...), (...)

How to ignore case?

Check the “Ignore Case” option to make pattern matching case-insensitive.