Free Online Regex Tester & Debugger
Free online tool to test and debug JavaScript regular expressions with real-time highlighting and match groups.
Initializing Module
Optimizing assets and preparing high-fidelity workspace...
How to use it
Enter Pattern
Type your regex pattern in the top field. Do not include the starting or ending slashes.
Select Flags
Toggle flags like Global (g), Case-insensitive (i), or Multiline (m) to adjust the matching behavior.
Insert Test Text
Paste your sample text in the input area to see matches highlighted in real-time in the preview panel.
FAQ
?Which Regex flavor is supported?
This tool uses the native JavaScript RegExp engine, which is the standard for web development and Node.js environments.
?Are my patterns and data private?
Yes. All regex processing happens entirely in your browser. No data or patterns are sent to our servers or stored anywhere.
?What do the flags do?
Flags modify how the search is performed. For example, 'g' finds all matches rather than just the first one, and 'i' makes the search ignore uppercase/lowercase differences.
Need a custom tool?
We're constantly adding new tools. Suggest one or report a bug.
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Your data never leaves your browser
Test and perfect your regular expressions with our free online Regex Tester. Get real-time visual highlighting of matches, explore capture groups, and analyze execution performance. Supports all standard JavaScript flags and provides instant feedback on syntax errors, making regex debugging effortless.