Regex Tester
Test regular expressions with real-time matching and detailed explanations.
Quick Reference
Enter a Pattern
Enter a valid regular expression pattern to test it against your text.
Understanding Regular Expressions
Regular Expression Basics
- Literal Characters: Most characters match themselves (e.g., 'a' matches 'a')
- Special Characters: . ^ $ * + ? { } [ ] \ | ( ) have special meanings
- Character Classes: [abc] matches any of a, b, or c
- Quantifiers: * (0+), + (1+), ? (0-1), {n,m} (between n and m)
- Anchors: ^ matches start of line, $ matches end of line
Common Use Cases
- Validate email addresses, phone numbers, and other formatted data
- Extract specific patterns from text (URLs, dates, etc.)
- Search and replace text with pattern matching
- Parse and validate user input in forms
- Clean and format data by matching unwanted patterns
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