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

r"
"
gim

Test String

Code Generator

Language

Generated Code

re = /'\$([\d]*)[\.]?(\d+)'/im str = '#Test-2019-8 #1.\'do+g\' dog, doooog, abcdogef, asdooooijk dooog asdoogghj \'dog\', \'doooog\', \'abcdogef\' #2. \'ab*d\' ad, abd, abbbd \'ad\', \'abd\', \'abbbbd\' \'sad\', \'cabd\', \'abbbds\' #3. \'[xy]{2}AB\' \'xxAB\', \'xyAB\',\'yyAB\' \'2xxAB\' #4. \'[a-z].?\' \'aA\', \'b9\', \'z\' \'bX\' \'aB z8 b6\' #5. \'5[abc]?ef\' \'5aef\', \'a5bef\', \'5ef\' \'5ef\' #6. Taiwan ID : \'([A-Z])([12])(\\d{8})\',\'[A-Z][12]\\d{8}\' \'A102926987\', \'B212345678\' #7. mobile tel_num:\'(09)(\\d\\d)[-\\s](\\d{3})[-\\s](\\d{3})\' \'0988 123 456\', \'0978-456-789\' # : \'09\\d\\d[-\\s]\\d\\d\\d\' \'0924-357\' #8. Home tel_num: # \'([\\(]?\\d\\d[\\)-]?)([\\d]{4})([-\\s]{1}[\\d]{4})\' \'(02)2257 3150\', \'02-2250-3457\',\'(12)2245 3214\' # \'[\\(]?(0[23])[\\)-]?(\\d{4})\' \'(02)2345\', \'03-1348\' #9. Date Time:yyyy/mm/dd #\'(20[12]\\d)[-\\/]([1]?[\\d])[-\\/]([1-3][\\d])\' \'2019/1/25\', \'2018-12-31\' #\'(20[12]\\d)[-\\/]([01]\\d)[-\\/](\\d{2})\' \'2019/01/15\' ,\'2020-11-28\' #10. floating number: \'\\$([\\d]*)[\\.]?(\\d+)\' \'$123.34\', \'$2345\' \'$0.234\' ,\'1.87\' ' # 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