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

%
%
ig

Test String

Code Generator

Language

Generated Code

$re = '%<a[^>]*?~dead host~.*?</a>%i'; $str = 'There is a bunch of text here. It sure is a pretty day outside. <a href=\'http://~dead host~/vypdye57f25o\' rel=\'nofollow\' target=\'blank\'>part-2</a> The sun is chirping, the birds are shining. It\'s a glorious day today, indeed. There once was a man from Nantucket, who kept all his cash in a bucket. <a href="http://www.google.com">Google.com</a> But his daughter named "Nan" ran away with a man and as for the bucket, Nan tuck it. <a href="http://~dead host~/asdf">Dead host</a>. Paw followed this pair to Nantucket, the mand and the girl with the bucket, and he said to the man, "You\'re welcome to Nan", but as for the bucket, Paw tuck it. <a href="http://www.yahoo.com">asdf</a>'; preg_match_all($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