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

/
/
gmx

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://www.timeslive.co.za/sunday-times/news/2020-11-01-hawks-following-former-steinhoff-ceo-markus-joostes-money/&amp;ct=ga&amp;cd=CAIyGjRm https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://www.politifact.com/factchecks/2020/oct/31/raphael-warnock/fact-checking-raphael-warnocks-claim-georgia-sen-k/&amp;ct=ga&amp;cd=CAIyGm https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://www.benzinga.com/news/20/10/18156683/last-weeks-notable-insider-buys-ibm-intel-raytheon-and-more&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://stocksregister.com/2020/10/31/insider-trading-at-avino-silver-gold-mines-ltd-nyseasm-what-did-we-note/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5Y https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://www.businessinsider.co.za/who-received-an-sms-from-markus-jooste-2020-10&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU3MWY2MDY6Y29tOmVuOlVT&am https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://stocksregister.com/2020/10/31/insider-trading-at-veritone-inc-nasdaqveri-what-did-we-note/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU3MWY2M https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://heavy.com/sports/las-vegas-raiders/jj-watt-stephon-gilmore-trade-targets/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU3MWY2MDY6Y29tOmVuOlVT&a https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://stocksregister.com/2020/10/31/insider-trading-at-truecar-inc-nasdaqtrue-what-did-we-note/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU3MWY2MD https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://stocksregister.com/2020/10/31/insider-trading-at-veeco-instruments-inc-nasdaqveco-what-did-we-note/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRl https://www.google.com/url?rct=j&amp;sa=t&amp;url=https://stocksregister.com/2020/10/31/insider-trading-at-21vianet-group-inc-nasdaqvnet-what-did-we-note/&amp;ct=ga&amp;cd=CAIyGmM3Yjk5YjRlYWU '; my $regex = qr/(?<=url=)https?:\S+?(?=&amp;|$)/mxp; 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