Regex Tester
Test regular expressions
How Regular Expression Testing Works
The Regex Tester lets you write, test, and debug regular expressions in real-time. Enter a pattern and test string to instantly see matches highlighted, capture groups extracted, and any syntax errors explained. It supports JavaScript regex syntax with all standard flags.
Key Features
- ✓Real-time match highlighting as you type
- ✓Capture group extraction and display
- ✓Support for global, case-insensitive, and multiline flags
- ✓Common regex pattern library for reference
Pro Tip
Build complex regex patterns incrementally \u2014 start with the simplest pattern that matches your target, then add specificity. Use non-capturing groups (?:...) when you need grouping but do not need to extract the match.
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