Regex Tester
Test regular expressions against sample text with real-time match highlighting. Supports flags and capture groups.
How to Use Regex Tester
The Regex Tester is a free online tool for testing regular expressions against sample text with real-time match highlighting. Write your regex pattern, enter test text, and instantly see all matches highlighted with capture group details. Supports all JavaScript regex flags including global (g), case-insensitive (i), multiline (m), and dotAll (s). Whether you are validating email formats, extracting data from log files, building input validation patterns, or learning regex syntax, this tool provides immediate visual feedback. Essential for developers, data engineers, and system administrators who work with pattern matching in code, scripts, and data processing.
Step-by-Step Instructions
- Enter your regular expression pattern
- Set any flags (global, case-insensitive, multiline)
- Paste or type the test text to match against
- View highlighted matches and capture group details in real-time
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