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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<li class="navItem "><a href="/services/" lang="de" hreflang="de">Services</a></li> <a class="iMacLink" href="/portfolio/" ><div class="iMacOverlay"></div><div class="">Super</div></a></div> <div class="addthis_toolbox addthis_default_style"> <a itemprop="url" target="_blank" href="https://www.facebook.com/any-profile" title="facebook" class="facebookSite"><span class="icon-facebook"></span></a> <a itemprop="url" target="_blank" href="https://twitter.com/any-profile" title="twitter" class="twitterSite"><span class="icon-twitter"></span></a> <a itemprop="url" target="_blank" href="https://pinterest.com/any-profile" title="pinterest" class="pinterestSite"><span class="icon-pinterest"></span></a> <a itemprop="url" target="_blank" href="//feeds.feedburner.comany-profile?format=xml" title="rss" class="rss"><span class="icon-rss"></span></a> </div> <a class="social facebookProfil" href="http://www.facebook.com/any-profile">Facebook</a> <a class="social facebookProfil" href=\'https://www.facebook.com/single-quotes\'>Facebook</a> <a class="social facebookProfil" href=https://www.facebook.com/no-quotes>Facebook</a> <a class="social youtubeProfil" href="http://www.youtube.com/user/any-profile">Youtube</a> <a class="social vimeoProfil" href="http://vimeo.com/any-profile">Vimeo</a> <a class="social xingProfil" href="https://www.xing.com/companies/any-profile">XING</a> <a class="social twitterProfil" href="https://twitter.com/any-profile">Folge bei Twitter</a> <a href="https://www.instagram.com/p/CN-Kx40nOW0/">Instagram Beitrag</a> <a href="http://instagram.com/quellenhofaachen">Instagram Profil</a> <a href="https://www.instagram.com/explore/tags/url">Instagram Tag-Url</a> <A href="https://www.Instagram.com/uppercase-link">Upercase-link</A> <a href="http://instagram.com/unique">Unique-test http</a> <a href="//instagram.com/unique">Unique-test protocol relative</a> <a href="https://instagram.com/unique">Unique-test https</a> <a href="http://www.instagram.com/unique">Unique-test www</a> '; my $regex = qr/<a[^>]*?href=(["\'])?((?:.(?!\1|>))*.?)\1?/ip; 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