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

/
/

Test String

Code Generator

Language

Generated Code

$re = '/^(?=.{173}\Q\2\)){2}.{11}$\E\/\z)((?=(.2.|))\2\/\2\^\2\(\2\?=\2\.\2\{173}\2\\\\Q\2\\\\2\2\\\\\2\)\2\)\2\{2}\2\.\2\{11}\2\$\2\\\\E\2\\\\\2\/\2\\\\z\2\)\2\(\2\(\2\?=\2\(\2\.2\2\.\2\|\2\)\2\)){2}.{11}$/'; $str = '/^(?=.{173}\\Q\\2\\)){2}.{11}$\\E\\/\\z)((?=(.2.|))\\2\\/\\2\\^\\2\\(\\2\\?=\\2\\.\\2\\{173}\\2\\\\Q\\2\\\\2\\2\\\\\\2\\)\\2\\)\\2\\{2}\\2\\.\\2\\{11}\\2\\$\\2\\\\E\\2\\\\\\2\\/\\2\\\\z\\2\\)\\2\\(\\2\\(\\2\\?=\\2\\(\\2\\.2\\2\\.\\2\\|\\2\\)\\2\\)){2}.{11}$/'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($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