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

$re = '#^(?P<major>\d+)(?:\.(?P<minor>\d+)(?:\.(?P<build>\d+)(?:\.(?P<revision>\d+))?)?)?(?:-(?P<prerelease>\w+)(?:[-\.](?P<version>\d+))?)?$#m'; $str = '1.0.10123.0 1.0.10123.0-preview 1.0.10123.0-beta-1 1.0.10123.0-beta.2 0.9-beta-2 2.1.0 2.1.1 2.1.1-preview 2.1.1-beta.1 2.1.1-rc-4 1.8.9 2.5.1 5.2.1 6.5 11.5 1.16 5.4.1.1 5.4.1.1 5.4.1.1 1.4 1.4.2 1.9.1.8 1.6.37 3.1 15 2 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15.112.1 15 15.112.1 15.112.1 15.112.1 17.14.15 17.14.15 17.8.8 1.1.2 1.1.2 1.1.1 15 13.0.3 5.4 15.0.2 15.0.2 15.0.2 15 1.3.6 1.1.1 8.5.2 3.0.0 9.0.107 9.0.537 9.0.537 9.0.537 4.2.0 9.0.0 9.0.1 9.0.0 6.0.0 3.0.0 7.0.0 3.0.0 1.8.11 1.0.119 5.2.3 6.1 6.1 22 1 1.0.3240.44 3.5.5 3.5.5-preview 3.5.5-preview.1 3.5.5-preview-2 3.2 3.2-beta'; preg_match_all($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