Regex Tester
Test and debug regular expressions with match highlighting
Match Information›
empty string✨ AIAssistant›
Explanation›
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Regex Tester & Debugger
Test and debug regular expressions with live match highlighting, group capture, and flag support. Works with JavaScript regex syntax. Paste your pattern, enter test text, and see matches instantly.
FAQ
What regex flags are supported?
g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky) — the same flags as JavaScript's RegExp.
How do I match a whole word?
Use word boundaries: \bword\b matches 'word' but not 'words' or 'keyword'.
How do I make a regex case-insensitive?
Add the i flag. /hello/i will match Hello, HELLO, hElLo, etc.
What is a capture group?
Parentheses create a capture group: (\d+) captures one or more digits. Named groups use (?<name>pattern).
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