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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '3 2 0.000040 10.65.170.58 192.168.200.1 TCP 54 80 56978 [RST] Seq=1 Win=0 Len=0\\n8 17.900574 192.168.200.1 10.65.170.58 HTTP 374 HEAD //web-console/ServerInfo.jsp HTTP/1.1\\n12 17.923315 192.168.200.1 10.65.170.58 HTTP 425 HEAD //jmx-console/HtmlAdaptor?action=inspectMBean&name=jboss.system:type=ServerInfo HTTP/1.1\\n23 39.938431 fe:ff:ff:ff:ff:ff 22:00:0a:41:aa:3a ARP 42 Who has 10.65.170.58? Tell 10.65.170.1\\n35 46.183360 192.168.200.1 10.65.170.58 HTTP 340 HEAD //invoker/JMXInvokerServlet HTTP/1.1\\n80 64.435331 10.65.170.58 69.89.27.239 TCP 74 51361 80 [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=1299648 TSecr=0 WS=16\\n79 64.378104 172.16.0.23 10.65.170.58 DNS 108 Standard query response 0xe1e0 A www.joaomatosf.com CNAME joaomatosf.com A 192.168.200.1\\n115 79.377537 192.168.200.1 10.65.170.58 HTTP 286 GET //jbossass/jbossass.jsp?ppp=uname+-a HTTP/1.1 2 0.000040 10.65.170.58 192.168.200.1 TCP 54 80 56978 [RST] Seq=1 Win=0 Len=0\\n8 17.900574 192.168.200.1 10.65.170.58 HTTP 374 HEAD //web-console/ServerInfo.jsp HTTP/1.1\\n12 17.923315 192.168.200.1 10.65.170.58 HTTP 425 HEAD //jmx-console/HtmlAdaptor?action=inspectMBean&name=jboss.system:type=ServerInfo HTTP/1.1\\n23 39.938431 fe:ff:ff:ff:ff:ff 22:00:0a:41:aa:3a ARP 42 Who has 10.65.170.58? Tell 10.65.170.1\\n35 46.183360 192.168.200.1s 10.65.170.58 HTTP 340 HEAD //invoker/JMXInvokerServlet HTTP/1.1\\n80 64.435331 10.65.170.58 69.89.27.239 TCP 74 51361 80 [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=1299648 TSecr=0 WS=16\\n79 64.378104 172.16.0.23 10.65.170.58 DNS 108 Standard query response 0xe1e0 A www.joaomatosf.com CNAME joaomatosf.com A 192.168.200.1\\n115 79.377537 192.168.200.1 10.65.170.58 HTTP 286 GET //jbossass/jbossass.jsp?ppp=uname+-a HTTP/1.1 2 0.000040 10.65.170.58 192.168.200.1 TCP 54 80 56978 [RST] Seq=1 Win=0 Len=0\\n8 17.900574 192.168.200.1a 10.65.170.58 HTTP 374 HEAD //web-console/ServerInfo.jsp HTTP/1.1\\n12 17.923315 192.168.200.1 10.65.170.58 HTTP 425 HEAD //jmx-console/HtmlAdaptor?action=inspectMBean&name=jboss.system:type=ServerInfo HTTP/1.1\\n23 39.938431 fe:ff:ff:ff:ff:ff 22:00:0a:41:aa:3a ARP 42 Who has 10.65.170.58? Tell 10.65.170.1\\n35 46.183360 192.168.200.1 10.65.170.58 HTTP 340 HEAD //invoker/JMXInvokerServlet HTTP/1.1\\n80 64.435331 10.65.170.58 69.89.27.239 TCP 74 51361 80 [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=1299648 TSecr=0 WS=16\\n79 64.378104 172.16.0.23 10.65.170.58 DNS 108 Standard query response 0xe1e0 A www.joaomatosf.com CNAME joaomatosf.com A 192.168.200.1\\n115 79.377537 192.168.200.1 1a0.65.170.58 HTTP 286 GET //jbossass/jbossass.jsp?ppp=uname+-a HTTP/1.1 '; my $regex = qr/[0-9]{1,3} [0-9]{1,3}\.[0-9]{6} 192\.168\.200\.1 ([0-9]{1,3}\.){3}[0-9]{1,3} HTTP .*?1\.1/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