Regex Tester
Test regular expressions against text in real time. Highlights matches visually with full group and capture support.
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Regex Cheat Sheet
Click a pattern to use it
How it works
Enter a regular expression pattern and test text. Matches are highlighted in yellow below.
Examples of use
- Validate email addresses, phone numbers, or URLs with regex
- Test pattern matching for data extraction
- Debug and refine regular expressions visually
When to use this tool?
- When building or debugging regular expressions
- When validating input patterns like emails or phone numbers
- When testing data extraction patterns
- When learning regex syntax
Frequently asked questions
- What is a regular expression?
- A regular expression (regex) is a sequence of characters that defines a search pattern. It is used for pattern matching within strings, commonly for validation, search, and replace operations.
- What flags are available?
- Common flags include: g (global - find all matches), i (case-insensitive), m (multiline), and s (dot matches newline).