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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'http://apne.ws/1nRjKS0 http://bit.ly/9H0CQT http://twitter.com/BBCTimWillcox http://www.bbc.co.uk/news/magazine-18529371 http://bbc.in/Mb1PWM http://bbc.in/PCXSFT http://nbcnews.to/ReH3pK http://www.breakingnews.com/topic/75-earthquake-off-alaska-january-2013 http://online.wsj.com/news/articles/SB10001424052702304908304579568590603893 http://on.cnn.com/13DsWkq http://cnnmon.ie/1GZiy8l http://reut.rs/1sOV13M http://on.fb.me/i1i3sT http://econ.st/fcUlsA http://on.wsj.com/SIji5s http://on.wsj.com/1J4Id3r https://word.office.live.com/wv/WordView.aspx?FBsrc=https%3A%2F%2Fwww.facebook.com%2Fattachments%2Ffile_preview.php%3Fid%3D713981818737203%26time%3D1453372782%26metadata&access_token=1604966176%3AAVKzw1ZzsEjWvtPbeu8TWvHPb3URXSaCRCdnoJsfz5TVnQ&title=2016+Stage+ILE+Simulation+d_un+syste_me+d_armes+sous+Simulink.doc https://www.facebook.com/groups/522095331140491/?multi_permalinks=1255982751085075&ref=notif&notif_t=group_highlights'; my $regex = qr/https?:\/\/(www.)?[a-zA-Z]+(\.[a-zA-Z]+)+(\/(\w|[-_%.#?=&+])+)+/p; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html