Regex Tester
Test regular expressions in real-time with highlighting
Matches (2)
What are Regular Expressions (Regex)?
Regex (Regular Expressions) are sequences of characters that form a search pattern. They are powerful tools for text manipulation, input validation (like emails and phone numbers), and data extraction (scraping).
Common Metacharacters
.: Matches any single character.*: Matches zero or more occurrences of the preceding element.+: Matches one or more occurrences.\d: Matches any numerical digit.^and$: Indicate the start and end of a line, respectively.
Security: The Danger of ReDoS
Poorly written expressions can lead to ReDoS (Regular Expression Denial of Service) attacks, where a complex query consumes 100% of the server's CPU. By testing here, you can validate the logic before implementing it in your backend.
Privacy: Test Locally
Often you need to test regex with real data that may contain sensitive user information or production logs. At Octovelo, your testing occurs entirely in your browser via JavaScript. Your test text and your regex pattern are never sent to our servers. Total security for your development workflow.