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

/
/
g

Test String

Code Generator

Language

Generated Code

$re = '/(?:(4\d{3}(?P<DelimVI>[\ \-]?)(?:\d{4}(?P=DelimVI)){2}\d(?:\d{3})?)|(5([1-5]\d{2})(?P<DelimMC>[\ \-]?)\d{4}(?P=DelimMC)\d{4}(?P=DelimMC)\d{4})|(3[47]\d\d(?P<DelimAX>[\ \-]?)\d{6}(?P=DelimAX)\d{5}))/'; $str = '"This is Visa number 4111111111111111, next is MasterCard number 5105105105105100, next is Amex 378282246310005" //Visa 13 or 16 digits with optional delimiters of spaces or dashes between number groups, e.g.“4012-8888-8888-1881” or “4012-8888-8888-1”. "//Master 16 digits with optional delimiters of spaces or dashes between number groups, e.g.“5112-8888-8888-1881” //American Express with optional matching delimiters of spaces or dashes between number groups, e.g. “3714-496353-98431” or “3714 496353 98431”, but not mix of delimeters “3714-496353 98431” . (4\\d{3}(?P<DELIM>[\\ \\-]?)(?:\\d{4}(?P=DELIM)){2}\\d(?:\\d{3})?) (?:(4\\d{3}(?P<DelimVI>[\\ \\-]?)(?:\\d{4}(?P=DelimVI)){2}\\d(?:\\d{3})?)|(5([1-5]\\d{2})(?P<DelimMC>[\\ \\-]?)\\d{4}(?P=DelimMC)\\d{4}(?P=DelimMC)\\d{4})|(3[47]\\d\\d(?P<DelimAX>[\\ \\-]?)\\d{6}(?P=DelimAX)\\d{5}))'; preg_match_all($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