Free Online Regular Expression Tester
Quick Tips
- • This tool runs entirely in your browser - your data stays private.
- • Press Ctrl+V (Cmd+V on Mac) to quickly paste text.
- • Use the Copy button to save your result to clipboard.
- • Bookmark this page for quick access!
Test and debug regular expressions with live matching.
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Examples
Pattern: \d+ Text: Order 12345 shipped
Match: 12345
Pattern: [a-z]+@[a-z]+\.[a-z]+ Text: contact@example.com
Match: contact@example.com
Pattern: ^Hello Text: Hello World
Match: Hello
Pattern: (\w+)@(\w+) Text: user@domain
Groups: user, domain
Why Use This Tool?
What problems does this solve?
Regular expressions are powerful but tricky to write correctly. Testing patterns against sample text with instant feedback helps build accurate expressions.
Common use cases:
- Testing regex patterns before implementing in code
- Debugging why patterns aren't matching expected text
- Learning regex syntax with immediate visual feedback
Who benefits from this tool?
Developers writing validation patterns. Data analysts extracting information from text. System administrators creating log parsing rules. Anyone learning or using regular expressions.
Privacy first: All processing happens in your browser. Your test data never leaves your device.
Frequently Asked Questions
Nearly all modern programming languages support regex including JavaScript, Python, Java, C#, PHP, Ruby, Go, and Perl. The syntax is largely similar across languages with some minor variations in features and escaping rules.
The global flag makes the regex engine find all matches in the text rather than stopping after the first match. Without it, only the first occurrence is matched.
Escape special characters with a backslash. To match a literal dot, use \. instead of just . which matches any character. Other special characters needing escaping include: * + ? [ ] ( ) { } ^ $ | \
The * quantifier matches zero or more occurrences (including no matches), while + requires at least one occurrence. For example, \d* matches empty strings, but \d+ requires at least one digit.
Yes, enable the multiline (m) flag to make ^ and $ match the start and end of each line, not just the entire string. The dotall (s) flag makes . match newlines for patterns spanning multiple lines.
Absolutely. All regex testing occurs locally in your browser. Your patterns and test text are never transmitted to any server, ensuring complete privacy for sensitive content.
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