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

/
/
gim

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'https://web.facebook.com https://google.com https://web.facebook.com/destiney.arkaden/posts/pfbid0jxqYa9Jkfoe9rATYUAcv9FsRnc1NGea2Kz6JxZPHKbe17xjS1akgEk5z6Z4tQTh2l?__cft__%5B0%5D=AZXy-D_E-IEYmmLc13KwLzY8E3AVjhlr1HRlJ1ejqqP1GqpRxK3ntzsoBEdpNopoBqAi_JHZJeZfYatg8ey4vsuU2vTHRjqxurMX6VYuVboZ9yAmDBWWWKdw87M6wai_ovqA-9bXektCQtxpAgNJCp0B&__tn__=%2CO%2CP-R; <div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">Wondering what it takes to study in Europe?</span></span></span></span></div><div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">Join </span></span></span></span><a href="https://setlinn.com/profile/63cb889363b41c3cd16b37e6" target="_blank" rel="noopener noreferrer"><span data-slate-node="element" data-slate-inline="true" data-slate-void="true" contenteditable="false" data-cy="mention-Mahtabuzzaman-Rangan" class="mentionedUser" style="padding: 3px 3px 2px; margin: 0px 1px; vertical-align: baseline; display: inline-block; border-radius: 4px; font-size: 0.9em; box-shadow: none;"><span data-slate-spacer="true" style="height: 0px; color: transparent; outline: currentcolor; position: absolute;"><span data-slate-node="text"><span data-slate-leaf="true"><span data-slate-zero-width="z" data-slate-length="21"></span></span></span></span>@Mahtabuzzaman Rangan</span></a><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">as we bring him live on Facebook tomorrow to explain the step-wise processes.</span></span></span></span></div><div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-zero-width="z" data-slate-length="0"></span></span></span></span><a href="https://setlinn.com/profile/63a042575380303f8d583116" target="_blank" rel="noopener noreferrer"><span data-slate-node="element" data-slate-inline="true" data-slate-void="true" contenteditable="false" data-cy="mention-Michael-Onwuatuegwu" class="mentionedUser" style="padding: 3px 3px 2px; margin: 0px 1px; vertical-align: baseline; display: inline-block; border-radius: 4px; font-size: 0.9em; box-shadow: none;"><span data-slate-spacer="true" style="height: 0px; color: transparent; outline: currentcolor; position: absolute;"><span data-slate-node="text"><span data-slate-leaf="true"><span data-slate-zero-width="z" data-slate-length="20"></span></span></span></span>@Michael Onwuatuegwu</span></a><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">will be on the session too.</span></span></span></span></div><div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-zero-width="n" data-slate-length="0"><br></span></span></span></span></div><div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">Link to join ⬇️ </span></span></span></span></div><div data-slate-node="element"><span data-slate-node="text"><span data-slate-leaf="true"><span><span data-slate-string="true">https://web.facebook.com/destiney.arkaden/posts/pfbid0jxqYa9Jkfoe9rATYUAcv9FsRnc1NGea2Kz6JxZPHKbe17xjS1akgEk5z6Z4tQTh2l?__cft__%5B0%5D=AZXy-D_E-IEYmmLc13KwLzY8E3AVjhlr1HRlJ1ejqqP1GqpRxK3ntzsoBEdpNopoBqAi_JHZJeZfYatg8ey4vsuU2vTHRjqxurMX6VYuVboZ9yAmDBWWWKdw87M6wai_ovqA-9bXektCQtxpAgNJCp0B&amp;__tn__=%2CO%2CP-R</span></span></span></span></div>'; my $regex = qr/(?:(?:https?|ftp|file):\/\/|www\.|ftp\.)(?:\([-A-Z0-9+&@#\/%=~_|$?!:,.]*\)|[-A-Z0-9+&@#\/%=~_|$?!:,.])*(?:\([-A-Z0-9+&@#\/%=~_|$?!:,.]*\)|[A-Z0-9+&@#\/%=~_|$])*(?:\([-A-Z0-9+&@#\/%=~_|$?!:,.]*\)|[A-Z0-9+&@#\/%=~_|$;-])*/imp; 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