Regex Tester
Test regular expressions in real-time with match highlighting.
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g global i case-insensitive m multiline s dotAll u unicode Test String
Highlighted Output
Matches will be highlighted here...
Match Results
Matches: 0
- No matches found
Privacy First: All regex testing happens locally in your browser. No data is sent to any server.
What is a Regular Expression?
Regular expressions (regex) are patterns used to match character combinations in strings. They're powerful tools for searching, replacing, and validating text. This tester uses JavaScript's regex engine, which supports features like capture groups, lookaheads, and Unicode properties.
Common Regex Patterns
\d+- One or more digits\w+- One or more word characters[a-zA-Z]+- One or more letters^.*$- Entire line\b\w+\b- Whole words only
Regex Flags Explained
- g (global): Find all matches instead of stopping at the first
- i (ignore case): Case-insensitive matching
- m (multiline): ^ and $ match line start/end
- s (dotAll): . matches newlines
- u (unicode): Enable full Unicode support
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