Regex Cheatsheet - Regular Expression Quick Reference
Quick reference for regular expression patterns. Character classes, quantifiers, anchors, and common patterns.
Negative Lookbehind (?<!abc)
AssertionMatches position NOT preceded by specified expression (ES2018+)
Pattern
(?<!abc)Examples
(?<!\$)\d+Match digits not after $
Matches: 50 in €50
(?<!\-)wordMatch "word" not preceded by hyphen
Matches: password
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