Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
gx

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'string str = @" 50de1696-8c63-4856-a204-7f4d93082da8 AB9B479D-3E48-49B7-A3B9-3BEC6ADEE344 d1ce1bec29434df09a03fc0605a2b481 DC9A9DA1D9D448DA8B9BDC401E20BA69 {8f60f165-38f9-42ad-95d2-22b746de1cba} {DC9A9DA1-D9D4-48DA-8B9B-DC401E20BA69} (f4e06eae-58d2-4daa-9f2d-917f622d23ea) (DC9A9DA1-D9D4-48DA-8B9B-DC401E20BA69) {0xB7D3E6C4,0x7FA6,0x4C48,{0xBA,0x0A,0x44,0x58,0x9D,0x14,0xE5,0x12}} {0xf3ffac91,0xc8cd,0x434d,{0x9f,0x2d,0x78,0x93,0x9b,0xa4,0x82,0x1d}} ";'; my $regex = qr/(?n)(?i:{[a-f\d]{8}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{12}})| (?i:\([a-f\d]{8}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{12}\))| (?i:[a-f\d]{8}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{4}-?[a-f\d]{12})| {0x[a-fA-F\d]{8},0x[a-fA-F\d]{4},0x[a-fA-F\d]{4},{0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2},0x[a-fA-F\d]{2}}} /xp; 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