Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

re = /\\"\d{1,3}cm\\"/m str = '"<?xml version=\\"1.0\\" standalone=\\"no\\"?>", "<svg xmlns=\\"http://www.w3.org/2000/svg\\" version=\\"1.1\\" width=\\"1250cm\\" height=\\"1250cm\\">", "<desc>9W43OV00W8JKMA1IJNEYAM1WTG9AZH8K10LC</desc>", "<g id=\\"HMLW03D1BYIQ\\" fill=\\"red\\">", "<rect x=\\"252cm\\" y=\\"252cm\\" width=\\"252cm\\" height=\\"252cm\\"/>", "<rect x=\\"72cm\\" y=\\"72cm\\" width=\\"72cm\\" height=\\"72cm\\"/>", "<rect x=\\"131cm\\" y=\\"131cm\\" width=\\"131cm\\" height=\\"131cm\\"/>", "<rect x=\\"228cm\\" y=\\"228cm\\" width=\\"228cm\\" height=\\"228cm\\"/>", "<rect x=\\"240cm\\" y=\\"240cm\\" width=\\"240cm\\" height=\\"240cm\\"/>", "<rect x=\\"232cm\\" y=\\"232cm\\" width=\\"232cm\\" height=\\"232cm\\"/>", "<rect x=\\"192cm\\" y=\\"192cm\\" width=\\"192cm\\" height=\\"192cm\\"/>", "<rect x=\\"0cm\\" y=\\"0cm\\" width=\\"0cm\\" height=\\"0cm\\"/>", "<rect x=\\"0cm\\" y=\\"0cm\\" width=\\"0cm\\" height=\\"0cm\\"/>", "<rect x=\\"0cm\\" y=\\"0cm\\" width=\\"0cm\\" height=\\"0cm\\"/>", "<rect x=\\"65cm\\" y=\\"65cm\\" width=\\"65cm\\" height=\\"65cm\\"/>", "<rect x=\\"81cm\\" y=\\"81cm\\" width=\\"81cm\\" height=\\"81cm\\"/>", "<rect x=\\"65cm\\" y=\\"65cm\\" width=\\"65cm\\" height=\\"65cm\\"/>", "<rect x=\\"80cm\\" y=\\"80cm\\" width=\\"80cm\\" height=\\"80cm\\"/>", "<rect x=\\"82cm\\" y=\\"82cm\\" width=\\"82cm\\" height=\\"82cm\\"/>", "<rect x=\\"81cm\\" y=\\"81cm\\" width=\\"81cm\\" height=\\"81cm\\"/>", "</g>"' # Print the match result str.scan(re) do |match| puts match.to_s end

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html