Regular Expressions 101

Save & Manage Regex

  • Current Version: 2
  • Save & Share
  • Community Library

Flavor

  • PCRE2 (PHP)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java
  • .NET 7.0 (C#)
  • Rust
  • PCRE (Legacy)
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests
Sponsors
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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'Windows IP Configuration Host Name . . . . . . . . . . . . : CheziAndSima-PC Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Hybrid IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : kramer.local Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Atheros AR8151 PCI-E Gigabit Ethernet Controller (NDIS 6.20) Physical Address. . . . . . . . . : 50-E5-49-CE-FC-EF DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::5cba:e9f2:a99f:4499%11(Preferred) IPv4 Address. . . . . . . . . . . : 10.0.0.1(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Lease Obtained. . . . . . . . . . : ™š 06 €…‚…‘ˆ 2016 20:35:49 Lease Expires . . . . . . . . . . : ‰…™Œ‰™‰ 09 €…‚…‘ˆ 2016 21:05:49 Default Gateway . . . . . . . . . : 10.0.0.138 DHCP Server . . . . . . . . . . . : 10.0.0.138 DHCPv6 IAID . . . . . . . . . . . : 240182601 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-19-7A-1F-FC-50-E5-49-CE-FC-EF DNS Servers . . . . . . . . . . . : 10.0.0.138 NetBIOS over Tcpip. . . . . . . . : Enabled Ethernet adapter Local Area Connection* 11: Connection-specific DNS Suffix . : kramer.local Description . . . . . . . . . . . : Juniper Networks Virtual Adapter Physical Address. . . . . . . . . : 02-05-85-7F-EB-80 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::8dfb:6d42:97e1:2dc7%19(Preferred) IPv4 Address. . . . . . . . . . . : 172.16.2.7(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : DHCPv6 IAID . . . . . . . . . . . : 436340101 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-19-7A-1F-FC-50-E5-49-CE-FC-EF DNS Servers . . . . . . . . . . . : 172.16.0.6 172.16.0.91 NetBIOS over Tcpip. . . . . . . . : Enabled Tunnel adapter isatap.{899E5284-7FD6-4831-B397-9BA931E543E1}: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Microsoft ISATAP Adapter Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Tunnel adapter Teredo Tunneling Pseudo-Interface: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Tunnel adapter isatap.kramer.local: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : kramer.local Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2 Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes '; my $regex = qr/(?<!-)(?:[0-9a-f]{2}[:-]){5}[0-9a-f]{2}(?!-)/ip; 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