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

/
/
Uis

Test String

Code Generator

Language

Generated Code

$re = '/<\!--\[if\s+lt\s+IE\s+\d][^>]*>(.*)<\!\[endif\]-->/Uis'; $str = ' rwerwerw <!--[if lt IE 9]> <script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script> <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script> <![endif]--> rwerwerwerwe <script type="text/javascript"> jQuery(window).on(\'load\', function() { new JCaption(\'img.caption\'); }); if (typeof RokBoxSettings == \'undefined\') RokBoxSettings = {pc: \'100\'}; jQuery(document).ready(function() { jQuery(\'.hasTooltip\').tooltip({"html": true,"container": "body"}); }); jQuery(document).ready(function (){ jQuery(\'.minicolors\').each(function() { jQuery(this).minicolors({ control: jQuery(this).attr(\'data-control\') || \'hue\', position: jQuery(this).attr(\'data-position\') || \'right\', theme: \'bootstrap\' }); }); }); jQuery(function(){ new JVMenu(\'#\',{ main: { delay: 300, duration: 300, effect: \'fade\', easing: \'linear\' }, sub: { delay: 300, duration: 300, effect: \'slide\', easing: \'linear\' }, responsive: 992 }); }) jQuery(function(){new JVTop();}); jQuery(function($){ }); </script> <!--[if lt IE 9]> <script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script> <script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script> <![endif]--> '; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($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