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

/
/
gmx

Test String

Code Generator

Language

Generated Code

$re = '/(?(DEFINE) (?<separator>\D?) (?<iin> # issuer identification number for 16 and 19 digit cards # MIR 220[0-4] # Mastercard | 222[1-9] | 22[3-9]\d | 2[3-6]\d{2} | 27[01]\d | 2720 | 5[1-5]\d{2} # JCB | 352[89] | 35[3-8]\d # Visa | 4\d{3} # Dankort | 5019 # Discover | 6011 | 622[1-9] | 64[4-9]\d | 65\d{2} # InterPayment | 63[7-9]\d # UnionPay | 62\d{2} # Maestro | 5[06-9]\d{2} | 6\d{3} # Troy | 9792 ) ) ## pattern begins here \b (?| (?: # 14 digits: XXXX-XXXXXX-XXXX # Diners Club (?: 30[0-5]\d | 36\d{2} ) (?<sep>(?&separator)) \d{6} \k<sep> \d{4} ) | (?: # 15 digits: XXXX-XXXXXX-XXXXX # American Express 3[47]\d{2} (?<sep>(?&separator)) \d{6} \k<sep> \d{5} ) | (?: # 16 digits: XXXX-XXXX-XXXX-XXXX (?&iin) (?<sep>(?&separator)) \d{4} \k<sep> \d{4} \k<sep> \d{4} ) | (?: # 19 digits: XXXXXXXXXXXXXXXXXXX (?&iin) \d{15} ) ) \b/mx'; $str = 'VISA: 4916-0964-6896-0680,4716 4897 5598 3394 4024007191458214;4929677677283453911 MasterCard: 5324-3523-3637-8594 2221 0059 1411 2881 2720993802486259 American Express (AMEX): 3417-364760-63463 3703,747943,64738 345620254969461 Discover: 6011;1100;7456;3157 6011|3448|8657|7515 6011549504486287170 JCB: 3535#1626#1193#3330 3537w2194w6345w7160 3544115541621080497 Diners Club - North America: 5550@6773@7664@9628 5498!9120!2137!8785 5418926330224156 Diners Club - Carte Blanche: 3038~338630~9862 3043 979928 4843 30514730539784 Diners Club - International: 3601-529450-0216 3684 740236 6092 36068539661053 Maestro: 5038-1482-6826-8317 6761 1161 5463 2772 5020976162959049 Visa Electron: 4175-0064-3983-6063 4844 2214 1640 8361 4508772794670888 InstaPayment: 6375-9237-0580-9744 6387 4000 3155 2203 6387679822589033 UnionPay: 6257-8903-9875-9366 6283348562159853 6234512468972678451 Failed Luhn: 4024007191458216 4929677677283453917 Unrecognized IIN: 7135865572496322 3719865572496325 0139865572496321 7019865572496321 Improper spacing: 4024-0071 9145-8214 4024-00719145-8214 4024-007-19145-8214 3051-4730-5397-84 40240071914582144024007191458214 Unexpected length: 34562025496943 3498348562489555 305147305397847 3051473053978442 498348562489551 49834856248955837 498348562489558367 49834856248955836445'; preg_match_all($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