Regex Tester
Test regular expressions with real-time matching and highlighted results. Supports all JavaScript regex features including flags, groups, and lookarounds.
About Regex Tester
Our online Regex Tester helps you write and test regular expressions in real-time. It highlights all matches in your test string and provides detailed information about each match including captured groups, match positions, and more.
Whether you are validating email addresses, extracting data from text, or building complex pattern matching logic, this tool makes it easy to verify your regular expressions before using them in production code.
Frequently Asked Questions
Is this tool free?
Yes, completely free with no registration required.
What regex engine is used?
Uses the native JavaScript RegExp engine, so results are identical to what you will get in your JavaScript code.
What are regex flags?
Flags modify regex behavior: g (global - find all matches), i (case-insensitive), m (multiline mode), s (dotAll - . matches newlines), u (unicode mode).