Write and test JavaScript regular expressions against your own sample text before adding them to an application. Matches update as you edit the pattern, making it easier to inspect flags, repeated matches, and capture groups. Use the highlighted output to spot overly broad patterns, missing escapes, and edge cases without sending the test text to a server.
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Test Regular Expressions
Test and debug JavaScript regular expressions in real-time. distinct highlighting for matches and groups. Fast, free, and 100% private browser tool.
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1
Pattern
Enter regex.
2
Text
Enter test string.
3
Review Results
Verify the output looks correct before using or downloading it.
4
Save Your Output
Click the download or copy button to export your results to your device or clipboard.
Key Features
JS Engine
Uses your browser's native RegEx engine.
Flags
Toggle Global (g), Case Insecret (i), Multiline (m).
Frequently Asked Questions
This tool uses the JavaScript Regular Expression engine supported by your browser.
Yes, if your modern browser supports them (most Chrome/Firefox versions do).
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