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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(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})" test_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 '\n" " 0207.gm.jetos.com help.2012hi.hk srv001.proxydns.com web.cyut.edu.tw\n" " zfcay1751.chinaw3.com svr01.passport.serveuser.com wt.ikwb.com 3dvideo.ru gate-usa.com wwwcnas.org\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html