The Complete Regex Cheat Sheet for 2026

Why Every Developer Needs Regex Regular expressions (regex) are one of the most powerful tools in a developer's toolkit. Whether you are validating user input, parsing log files, or performing search-and-replace operations, regex lets you match complex text patterns with concise syntax. This cheat sheet covers everything from the basics to advanced techniques. Basic Character Classes Pattern Matches Example . Any character except newline a.c matches abc , a1c \d Any digit (0-9) \d{3} matches 123 \D Any non-digit \D+ matches abc \w Word character (a-z, A-Z, 0-9, _) \w+ matches hello_42 \W Non-word character \W matches @ \s Whitespace (space, tab, newline) \s+ matches spaces \S Non-whitespace \S+ matches hello [abc] Any of a, b, or c [aeiou] matches vowels [^abc] Not a, b, or c [^0-9] matches non-digits [a-z] Range: a through z [A-Za-z] matches letters Quantifiers Pattern Meaning Example * 0 or more ab*c matches ac , abc , abbc + 1 or more ab+c matches abc , abbc but not ac ? 0 or 1 (opt