regex-cheat-sheet

My go to regex cheatsheet to help me reading other people regex

Ranges

All Ranges are inclusive

• [a-z] ⇒ from a to z lower case only
• [A-Z] ⇒ from A to Z upper case only
• [0-9] ⇒ from 0 to 9
• [a-f] ⇒ from a to f
• [g-p] ⇒ from g to p
• [#$%&@] ⇒ any of those symbols
• [a-zA-Z0-9] ⇒ all digits, lower and upper case letters.

Repeat exact

using the {} curly braces notation

• a{5} ⇒ will match “aaaaa”.
• n{3} ⇒ will match “nnn”.
• [a-z]{4} ⇒ will match any four-letter word such as
• [a-z]{6,} ⇒ will match any word with six or more letters.
• [a-z]{8,11} ⇒ will match any word between eight and 11 letters.
• [0-9]{11} ⇒ will match an 11-digit number.

Generic selectors

• \d ⇒ matches any digit that is the same as [0-9]
• \w ⇒ matches any letter, digit and underscore character
• \s ⇒ matches a whitespace character — that is, a space or tab
• \t ⇒ matches a tab character only
• . ⇒ match any digit, letter or symbol except newline.

Special Characters (nasty ones)

• + ⇒ One or more
• ? ⇒ Zero or one
• * ⇒ Zero or more. It’s like the combination of + and ?.
• \ ⇒ escape character
• [^] ⇒ logical not or except

• **	** (pipe char) ⇒ logical or

• () ⇒ group together
• ^ ⇒ start of a string.
• $ ⇒ end of the string.