Regex Tester – Online Regular Expression Sandbox | ToolTree
Test and debug regular expressions instantly with live highlighting. ToolTree provides a secure, client-side regex tester for JavaScript developers.
Regex Tester
Test your regular expressions against sample text with real-time matching. Debug patterns, verify capture groups, and refine your logic securely in your browser.
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Test String
Match Result
Enter a pattern to see matches
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Regular Expression Basics
Regex is a sequence of characters that forms a search pattern. When you search for data in text, you can use this search pattern to describe what you are looking for. It can be a single character, or a more complicated pattern.
Common Flags
- g (global): Find all matches rather than stopping after the first match.
- i (ignore case): Case-insensitive matching.
- m (multiline): Treat beginning and end characters (^ and $) as working over multiple lines.