How to use the Regex Tester
1
Write Regex
Enter your regular expression pattern and flags in the top input fields.
2
Input Data
Paste the text you want to test against in the test string area.
3
See Results
Watch as matches are highlighted in real-time and details appear on the right.
Master Regular Expressions
Regular expressions (Regex) are powerful tools for pattern matching and text manipulation. Whether you're validating emails, scraping data, or refactoring code, our tester provides the visual feedback you need to build patterns with confidence.
Real-time Syntax Highlighting
Capture Group Support
Instant Privacy (Local Processing)
/pattern/g
Regex Tester Features
Live Testing
See matches and groups update instantly as you modify your regex or test string.
Private & Secure
Your data never leaves your computer. All processing happens locally in your browser.
Regex FAQ
What are regex flags?
Flags modify how the search is performed. Common ones include g (global - find all matches), i (case-insensitive), and m (multiline).
How do I capture groups?
Use parentheses
(...) to create capture groups. These allow you to isolate specific parts of a match, which are displayed in the results panel.