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

$re = '/(?=((?=(.{9})(.*))((.)(?=((?!\5).)*\3$)){9})*$)(?=((?=((.)(?=(.{8}(?!\9).)*.{0,8}$).{8}){8}).){9})(((?=(?=.{21}(.*))((.)(?=((?(?=(...)*$).{6})(?!\15).)*\13$)(?(?=(...)*$)(.{6}|.*))){9})...){3}.{18})+$/m'; $str = '123456789456789123789123456231564897564897231897231564312645978645978312978312645 725893461841657392396142758473516829168429537952378146234761985687935214519284673 395412678824376591671589243156928437249735186738641925983164752412857369567293814 679543182158926473432817659567381294914265738283479561345792816896154327721638945 867539142324167859159482736275398614936241587481756923592873461743615298618924375 954217683861453729372968145516832497249675318783149256437581962695324871128796534 271459386435168927986273541518734269769821435342596178194387652657942813823615794 237541896186927345495386721743269158569178432812435679378652914924813567651794283 168279435459863271273415986821354769734692518596781342615947823387526194942138657 863459712415273869279168354526387941947615238138942576781596423354821697692734185 768593142423176859951428736184765923572389614639214587816942375295837461347651298 243561789819327456657489132374192865926845317581673294162758943735914628498236571 243156789519847326687392145361475892724918653895263471152684937436729518978531264 498236571735914628162758943581673294926845317374192865657489132819327456243561789 978531264436729518152684937895263471724918653361475892687392145519847326243156789 341572689257698143986413275862341957495726831173985426519234768734869512628157394 519284673725893461841657392396142758473516829168429537952378146234761985687935214 839541267182437659367158924715692843624973518573864192298316475941285736456729381 679543182158926473432817659567381294914256738283479561345792816896154327721638945 867539142324167859159482736275398684936241517481756923592873461743615298618924375 754219683861453729372968145516832497249675318983147256437581962695324871128796534 271459386435168927986273541518734269769828435342596178194387652657942813823615794 237541896186927345378652914743269158569178432812435679495386721924813567651794283 168759432459613278273165984821594763734982516596821347615437829387246195942378651 869887283619214453457338664548525781275424668379969727517385163319223917621449519 894158578962859187461322315913849812241742157275462973384219294849882291119423759 123456789456789123564897231231564897789123456897231564312645978645978312978312645 145278369256389147364197258478512693589623471697431582712845936823956714931764825 243561789829317456657489132374192865916845327581673294162758943735924618498236571 243156789529847316687392145361475892714928653895263471152684937436719528978531264 498236571735924618162758943581673294916845327374192865657489132829317456243561789 978531264436719528152684937895263471714928653361475892687392145529847316243156789 342571689257698143986413275861342957495726831173985426519234768734869512628157394 345678192627319458892451673468793521713524986951862347179246835534187269286935714 341572689257698143986413275862341957495726831173985426519234768734869512628517394 '; 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