Regex Cheatsheet - Regular Expression Quick Reference
Quick reference for regular expression patterns. Character classes, quantifiers, anchors, and common patterns.
Positive Lookbehind (?<=abc)
AssertionMatches position preceded by specified expression (ES2018+)
Pattern
(?<=abc)Syntax
Explanation
Positive lookbehind checks preceding text. Note variable-length lookbehind support varies.
Examples
(?<=\$)\d+Match digits after $ sign
Matches: 100 in $100
(?<=@)\w+Match username after @
Matches: example in @example
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