build and test regular expressions with real-time feedback. supports multiple flags and client-side evaluation.
Matches Found
Evaluated in real-time on your device using the browser's native regex engine.
Regular Expressions (RegEx) are a powerful tool for string matching and data validation, but they are notoriously difficult to write and debug. Our free online regex tester provides a distraction-free playground to build and verify your patterns. Supporting the JavaScript RegEx engine, our tool allows you to instantly see how many matches your pattern finds in a sample text block, while providing real-time syntax validation.
This tool uses the standard JavaScript (V8) RegExp engine provided by your browser. While most regex syntax is universal, some advanced features like lookbehind or named groups may behave differently than in engines like PCRE (PHP) or Python.
No. All evaluation happens in your browser's memory. rizentium is built on a zero-log architecture, ensuring that your test data and proprietary patterns remain completely private.