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

$re = '/^(?!.*(\.com?\.)|\.com\.).*$/m'; $str = 'regexp_repalce with negated character class: yahoo\\.co[^\\.].* https://stackoverflow.com/questions/977251/regular-expressions-and-negating-a-whole-character-group ^(?!.*ab).*$ .es yahoo.es yahoo.fr yahoo.ca yahoo.cm yahoo.cn yahoo.tw yahoo.co.jp yahoo.co.kr yahoo.co.uk yahoo.com.cn yahoo.com.hk yahoo.com.mx yahoo.com.tw REPLACE yahoo.co yahoo.co, yahoo.com yahoo.com, yahoo.com. yahoo.com\' yahoo.com/haltokariev yahoo.com> yahoo.com21yahoo.com yahoo.comcom yahoo.comheatdoc1123 yahoo yahoomail.com keep yahool.com yahooo.com yahoo.comj yahoo.net yahoocom yahoo.com.hk yahoo.co.uk yahoo.es yahoo.co yahoo.com.tw yahoo.fr yahoo.ca gmasucciarchitects.com gmirealtyllc.com gmarchitects.nett gmarchitects.nte gmachitects.net gmarchitects.net g-mail.com g.mail.com gailmail.com gamail.com gaol.com geeemail.com gemail.com gfmail.com ggmail.com gimail.com gmai.com gmai9l.com gmaiil.com gmail gmail. gmail..com gmail.c gmail.cim gmail.cm gmail.co gmail.com gmail.com. gmail.com.com gmail.com101 gmail.com2014505140 gmail.com8206 gmail.comalexandrasceboldsecretary gmail.comaol.com gmail.combchan43460 gmail.comc gmail.comceciliaschiera gmail.comcolecole.cc1 gmail.comi gmail.comil.com gmail.comj gmail.comjamesesber gmail.coml.com gmail.comleponto gmail.comll gmail.comlwilliams102 gmail.comm gmail.comment.com gmail.commipg820 gmail.comn gmail.comnaka gmail.comnr.aidan.collins gmail.comol.com gmail.comorapa0013 gmail.con gmail.coom gmail.cpm gmail.cvom gmail.gmail.com gmail.net gmail.om gmail.oom gmail.you gmail1.com gmail8203.com gmailc.com gmailc.om gmailcom gmailfurman.com gmaill.com gmaillcom gmailmgmtcom gmails.com gmailus.com gmaiol.com gmal.com gmale.com gmall.com gmaol.com gmauil.com gmial.com gmil.com gmila.com gmmail.com'; 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