🔍 Regex Tester
Test and debug regular expressions with real-time pattern matching and highlighting. Perfect for developers validating input patterns, extracting data, and testing complex regex patterns.
📊 Highlighted Matches:
Enter text and regex pattern, then click "Test Regex" to see highlighted matches...
💡 How to use:
- Enter sample text you want to search in the textarea
- Enter your regex pattern in the pattern field
- Optionally add flags (g=global, i=ignore case, m=multiline, s=dotall)
- Click "Test Regex" to see highlighted matches
- Matches will be highlighted in yellow
- Error messages will display if the regex is invalid
📝 Common Regex Patterns:
| Pattern | Description | Example |
|---|---|---|
| \d+ | One or more digits | 123, 4567 |
| [a-z]+ | One or more lowercase letters | hello, world |
| [A-Z]+ | One or more uppercase letters | HELLO, WORLD |
| [a-zA-Z0-9]+ | Alphanumeric characters | abc123, XYZ789 |
| \w+ | Word characters (letters, digits, underscore) | hello_world, test123 |
| \s+ | Whitespace characters | spaces, tabs, newlines |
| [a-z]+@[a-z]+\.[a-z]+ | Simple email pattern | user@example.com |
| ^https?:\/\/ | HTTP/HTTPS URLs | https://example.com |
| \b\w{3,}\b | Words with 3+ characters | hello, world |
| ^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$ | IP Address pattern | 192.168.1.1 |
📚 Regex Flags:
- g - Global: Find all matches (not just first)
- i - Ignore Case: Case-insensitive matching
- m - Multiline: ^ and $ match line breaks
- s - Dotall: . matches newlines
- gi - Combine flags: Global + Ignore Case
💡 Tip: Always use the 'g' flag to find all matches in your text. Without it, only the first match is found.