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🧪 Regex Tester & Visualizer
Engine:
Live matching, groups, replace preview, and split. Save your test cases locally.
Flags
Quick Regex Cheat Sheet
- \d digit, \w word, \s whitespace
- . any char (add s for dotall)
- [abc] set; [^abc] negated set
- (a|b) alternation
- ^ start, $ end (add m for multiline)
- a? 0–1; a* 0+; a+ 1+
- Captures: ( ), non-capture: (?: )
- Named: (?<name>...) (PHP/PCRE), (?<name>...) (JS)
- Lookahead: (?=...), negative: (?!...)
- Lookbehind (supported in modern JS/PCRE): (?<=...) / (?<!...)
- Unicode property: \p{L} (add u)
Highlights
Matches & Groups
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Replace Preview
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