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 = '/(?:http?s?:\/\/)?(?:www.)?(?:m.)?(?:music.)?youtu(?:\.?be)(?:\.com)?(?:(?:\w*.?:\/\/)?\w*.?\w*-?.?\w*\/(?:embed|e|v|watch|.*\/)?\??(?:feature=\w*\.?\w*)?&?(?:v=)?\/?)([\w\d_-]{11})(?:\S+)?/m'; $str = 'https://www.youtube.com/watch?v=RCGGG9piAGY asdfasdfsadfsdf http://www.youtube.com/watch?v=iwGFalTRHDA http://www.youtube.com/watch?v=iwGFalTRHDA&feature=related http://youtu.be/iwGFalTRHDA http://youtu.be/n17B_uFF4cA http://www.youtube.com/embed/watch?feature=player_embedded&v=r5nB9u4jjy4 http://www.youtube.com/watch?v=t-ZRX8984sc http://youtu.be/t-ZRX8984sc https://www.youtube.com/attribution_link?a=tolCzpA7CrY&u=%2Fwatch%3Fv%3DMoBL33GT9S8%26feature%3Dshare https://www.youtube.com/watch?v=MoBL33GT9S8&feature=share http://www.youtube.com/watch?v=iwGFalTRHDA https://www.youtube.com/watch?v=iwGFalTRHDA http://www.youtube.com/watch?v=iwGFalTRHDA&feature=related http://youtu.be/iwGFalTRHDA http://www.youtube.com/embed/watch?feature=player_embedded&v=iwGFalTRHDA http://www.youtube.com/embed/watch?v=iwGFalTRHDA http://www.youtube.com/embed/v=iwGFalTRHDA http://www.youtube.com/watch?feature=player_embedded&v=iwGFalTRHDA http://www.youtube.com/watch?v=iwGFalTRHDA www.youtube.com/watch?v=iwGFalTRHDA www.youtu.be/iwGFalTRHDA youtu.be/iwGFalTRHDA youtube.com/watch?v=iwGFalTRHDA http://www.youtube.com/watch/iwGFalTRHDA http://www.youtube.com/v/iwGFalTRHDA http://www.youtube.com/v/i_GFalTRHDA http://www.youtube.com/watch?v=i-GFalTRHDA&feature=related http://www.youtube.com/attribution_link?u=/watch?v=aGmiw_rrNxk&feature=share&a=9QlmP1yvjcllp0h3l0NwuA http://www.youtube.com/attribution_link?a=fF1CWYwxCQ4&u=/watch?v=qYr8opTPSaQ&feature=em-uploademail http://www.youtube.com/attribution_link?a=fF1CWYwxCQ4&feature=em-uploademail&u=/watch?v=qYr8opTPSaQ http://www.youtu/v/i_GFalTRHDA https://www.youtube.com/watch?v=RCGGG9piAGYUt Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.https://www.youtube.com/watch?v=RCGGG9piAGYUt enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillumdolore eu fugiat nulla pariatur.https://i.stack.imgur.com//VFMIw.jpg?s=128\\u0026g=1\\u0026g\\u0026s=32Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.'; 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