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
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • 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 = '/(((20[012]\d|19\d\d)|(1\d|2[0123]))-((0[0-9])|(1[012]))-((0[1-9])|([12][0-9])|(3[01])))|(((0[1-9])|([12][0-9])|(3[01]))-((0[0-9])|(1[012]))-((20[012]\d|19\d\d)|(1\d|2[0123])))|(((20[012]\d|19\d\d)|(1\d|2[0123]))\/((0[0-9])|(1[012]))\/((0[1-9])|([12][0-9])|(3[01])))|(((0[0-9])|(1[012]))\/((0[1-9])|([12][0-9])|(3[01]))\/((20[012]\d|19\d\d)|(1\d|2[0123])))|(((0[1-9])|([12][0-9])|(3[01]))\/((0[0-9])|(1[012]))\/((20[012]\d|19\d\d)|(1\d|2[0123])))|(((0[1-9])|([12][0-9])|(3[01]))\.((0[0-9])|(1[012]))\.((20[012]\d|19\d\d)|(1\d|2[0123])))|(((20[012]\d|19\d\d)|(1\d|2[0123]))\.((0[0-9])|(1[012]))\.((0[1-9])|([12][0-9])|(3[01])))/m'; $str = 'work: 2022-01-01 01-01-2020 1990/01/01 12/30/2020 30/12/2020 30.12.2020 2020.12.30 19-12-30 30-12-19 2020/12/30 12/30/19 30/12/19 30.12.19 19.12.30 not work: 1022-01-01 01-15-2020 2990/01/01 13/30/2020 30/13/2020 30.12.9029 2020.14.30 2020.12.33 19-12-33 19-13-30 33-12-19 30-12-35 2020/13/30 2020/12/34 12/30/29 30/12/29 30.12.26 30.12.30 13/30/19 30/13/19 30.13.19 19.13.30 12/33/19 33/12/19 33.12.19 19.12.33 1/1/19 1/01/19 01/1/19 1/01/2019 1/1/2019 01/1/2019 '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php