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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

use strict; my $str = '\' Hashes Loaders - Trojan.MSIL.NERAPACK 12425edb2c50eac79f06bf228cb2dd77bb1e847c4c4a2049c91e0c5b345df5f2 321febf2bc5603b58628e3a82fb063027bf175252a3b30869eccb90a78e59582 3ad24a438b9a67e4eff7ca7d34b06d5efc24b824e3e346488d534532faa619da dd1afc083b7d82444fcec99e01e8293d51f744201cb968346ec334fb5dd32495 e488f0015f14a0eff4b756d10f252aa419bc960050a53cc04699d5cc8df86c8a 6b1b231a7d190651f8c89072e2514aade288dfe6bd87ea62171b6ecffe13d63e e4a15537f767332a7ed08009f4e0c5a7b65e8cbd468eb81e3e20dc8dfc36aeed a64e0c21494811ededf5d8af41b00937c1d5787d63dfcc399a7f32c19a553c99 Backdoors - Backdoor.Win64.CHISERCLIENT ea2264f56ba315c4db49d06cce12365875502686f8f748570cb5a99cb213f008 182f07a00b93a00fae17b33fbfc25931afeddd80f075f241060b4338a49cd5cc 2167855743b9e488ce514c80f246fd5d0973a4296cb565f95517fa1dcfee8f74 Trojan.Win32.SMILESVRDRP c6cac51035ef7df22c8ff3b5ba204721cdae97bc4728b0de68db1358c0c04035 Backdoor.Win32.SMILESVR c6f17d39905d2006020c326c13bb514a66bccc5a42d533aade00e09456ca5dec 97e9bf8032e11bb618a77fbe92489e972b0c92e2e30b26f594f6129ee1cec987 507b0280105da31739159703e418e3d1b1e6e6817362bf69e2da3c0b305af605 819afbdc46b3b8f3e4b71e64c48df14ce886a273ce3c93d7a402f4760405b1a4 Backdoor.Win64.LILITH b3c31192048576591a52bc025e82286d7d32429c2f0991e68d801555b2d74c65 Backdoor.Win32.GH0ST 996aa9c937b610efd1ab5c0ab173fc9fa78a70b423a193c3e2b505519bde7807 7e72ee1052b018250810e41ac01065ebd833293ecfc363415b7d19dd31734d49 Hacking tools HackTool.MSIL.LOGKILLER b914087ac90f8aa782ef4c22cee9c458f7bdfc3d37278327aa7e1442011f0e4a HackTool.Win64.FRP 7ca64c811008e34b5dbb7538fa4bed84c1678ed9813e665071dc0ad0def5b74b C&C Servers lastest.ctotw.tw:443 infos.friendship.tw:80 citilink.dsmtp.com:443 flight.goldentop.tw:80 cart.ns02.us webadmin.mirrorstorage.org:443 api01.lflinkup.net:80 portal.blueraymax.com:80 ca.threatiy.com:443 cb.threatiy.com:8443 cc.threatiy.com:8080 193.42.40.126 157.119.234.100 158.247.199.191 45.77.214.244 195.123.221.7:8080 \' 0207.gm.jetos.com help.2012hi.hk srv001.proxydns.com web.cyut.edu.tw zfcay1751.chinaw3.com svr01.passport.serveuser.com wt.ikwb.com 3dvideo.ru gate-usa.com wwwcnas.org '; my $regex = qr/(http|https|www\d{0,3}|)((\.|[a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-\_]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9]|\.)([a-z]{2,5})/mp; 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