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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<ipaddress>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}) - - \[(?P<dateandtime>\d{2}\/[a-z]{3}\/\d{4}:\d{2}:\d{2}:\d{2} (\+|\-)\d{4})\] (((\""(GET|POST|PUT|PATCH|DELETE|OPTIONS|HEAD|TRACE|CONNECT|[.*\\x.*]) )(?P<url>.+)(http\/1\.(1|0)""))|.*\\x.*) (?P<statuscode>(301|4(44|03|00))) (?P<bytessent>\d+) ([""](?P<refferer>(\-)|(.+))[""]) ([""](?P<useragent>.+)[""])"; string input = @"51.159.23.43 - - [30/Apr/2021:15:26:20 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""-"" 89.248.170.22 - - [30/Apr/2021:15:26:31 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:76.0) Gecko/20100101 Firefox/76.0"" 172.104.242.173 - - [30/Apr/2021:15:43:51 +0800] ""\xBA\xABd\xA1EZC\xDBM\x87\xEE^\xFD\xBF\x159 X\xD4>\x12\x98\xC4<\xE0\x13\xCF\x00\xAC\xA09\xD7\x90#8~\x8C\xDE\x9DReF\xBF%1Q\xE0\x9D\x06&g\xBB\x82\x95\x19\xED\x07\x14\x19ZP\x80+\x94e\xC3\xE6\x85\x06\xA4\x99\x8B\x19l\x01\xEA\x88Y\x91\x16\x95\xC4\xC8\x0EH\x02\xC7\x93g\xC14FW\x05|\xFB\xF3T\xB8\xFD\xCB\xBB)\xE3\xCE\xDD\xCD7\x9E\xEFP\x8C\xA4[V\xFD\x98\xC9l\x82\xF5\xE4\xC1d\x87X\xF7\x9B\xBF\xE8q\x12\x99&\xDB,\xF5\x87\xD7\xA8\x97j;\xE3\xEA\xA7\xB4\xB0\x02\xAD\x8DE\x9B\xAAB\x80\x0E)\xA9\xE9\xAF}\x18\x8E\xB8\x1E\x99\x04\xEF\xA8\x8C\xE8\x04\xE2\xD3\xED)1\x91\xC1\x8F\x88\x8C\x81\xF0\xDB\xA5\x88\x95H\x9BZ\xAB\xCE\xBF\xF4E%P*\x88KFY6\x9E\xE7::j\xD4\x8A\xA8V\x9A\xAA\xAB\xAF\xC3&.\xED[\x04\xC5e\x7F\x08\xBE\x8Ar\xA7\xB0\x99F\xF7\x11\xE5\xD6\x96\x8CIm+w\x1C\xFDuU\x14\x0F!x\xAC\xE8MPy\xC3\x19!2\xA0\xED\xC0}!Rw\x14\x8E\x1B\xC4\xE1\xA0\xAF+\xADKk\xC5\xE0\x5Cs\x9C\xBD\xCB"" 400 150 ""-"" ""-"" 192.241.216.138 - - [30/Apr/2021:16:57:52 +0800] ""GET /portal/redlion HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 zgrab/0.x"" 193.118.53.194 - - [30/Apr/2021:17:00:02 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:35 +0800] ""GET /vendor/phpunit/phpunit/src/Util/PHP/eval-stdin.php HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:35 +0800] ""POST /vendor/phpunit/phpunit/src/Util/PHP/eval-stdin.php HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:38 +0800] ""GET /index.php?s=/Index/\x5Cthink\x5Capp/invokefunction&function=call_user_func_array&vars[0]=md5&vars[1][]=HelloThinkPHP21 HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:40 +0800] ""GET /?XDEBUG_SESSION_START=phpstorm HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:41 +0800] ""POST /mifs/.;/services/LogService HTTP/1.1"" 444 0 ""https://125.160.120.137:443"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:43 +0800] ""GET /wp-content/plugins/wp-file-manager/readme.txt HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:44 +0800] ""GET /console/ HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:45 +0800] ""POST /Autodiscover/Autodiscover.xml HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:47 +0800] ""GET /_ignition/execute-solution HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 45.155.205.84 - - [30/Apr/2021:17:09:47 +0800] ""POST /api/jsonws/invoke HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36"" 89.248.170.22 - - [30/Apr/2021:17:23:51 +0800] ""HEAD / HTTP/1.0"" 444 0 ""-"" ""-"" 192.241.220.215 - - [30/Apr/2021:17:26:46 +0800] ""GET /actuator/health HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 zgrab/0.x"" 128.14.133.58 - - [30/Apr/2021:17:40:03 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36"" 74.120.14.37 - - [30/Apr/2021:17:41:07 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""-"" 74.120.14.37 - - [30/Apr/2021:17:41:09 +0800] ""GET / HTTP/1.1"" 400 248 ""-"" ""-"" 74.120.14.37 - - [30/Apr/2021:17:41:09 +0800] ""GET / HTTP/1.1"" 400 248 ""-"" ""Mozilla/5.0 (compatible; CensysInspect/1.1; +https://about.censys.io/)"" 192.241.212.72 - - [30/Apr/2021:18:36:39 +0800] ""GET /hudson HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 zgrab/0.x"" 189.39.247.159 - - [30/Apr/2021:19:01:06 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36"" 80.82.77.192 - - [30/Apr/2021:19:18:14 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36"" 80.82.77.192 - - [30/Apr/2021:19:22:45 +0800] ""GET / HTTP/1.1"" 400 248 ""-"" ""Mozilla/5.0 zgrab/0.x"" 190.94.151.114 - - [30/Apr/2021:19:40:19 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"" 92.118.161.21 - - [30/Apr/2021:19:47:03 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""NetSystemsResearch studies the availability of various services across the internet. Our website is netsystemsresearch.com"" 128.14.211.186 - - [30/Apr/2021:19:58:55 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36"" 119.15.88.56 - - [30/Apr/2021:20:46:18 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36"" 34.77.163.42 - - [30/Apr/2021:20:47:53 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""python-requests/2.25.1"" 194.62.6.193 - - [30/Apr/2021:20:56:30 +0800] ""HEAD / HTTP/1.0"" 444 0 ""-"" ""-"" 209.141.33.74 - - [30/Apr/2021:20:57:03 +0800] ""POST /boaform/admin/formLogin HTTP/1.1"" 444 0 ""http://125.160.120.137:80/admin/login.asp"" ""Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko/20100101 Firefox/71.0"" 216.21.170.197 - - [30/Apr/2021:21:09:26 +0800] ""GET /admin/login.asp HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 213.163.23.68 - - [30/Apr/2021:21:09:26 +0800] ""GET /:80/admin/login.asp HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 63.117.14.69 - - [30/Apr/2021:21:09:27 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 195.111.111.68 - - [30/Apr/2021:21:09:28 +0800] ""GET /admin/login.asp HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36"" 98.124.44.196 - - [30/Apr/2021:21:19:28 +0800] ""GET /:443 HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 128.14.133.58 - - [30/Apr/2021:21:25:18 +0800] ""GET / HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36"" 64.246.133.4 - - [30/Apr/2021:21:27:28 +0800] ""GET /:443 HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 24.220.112.166 - - [30/Apr/2021:21:43:28 +0800] ""GET /admin/login.asp HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" 64.53.1.196 - - [30/Apr/2021:21:47:29 +0800] ""GET /admin/login.asp HTTP/1.1"" 444 0 ""-"" ""Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.90 Safari/537.36"" "; RegexOptions options = RegexOptions.IgnoreCase | RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx