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

/
/
gi

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<p>qweq</p> <p>weq</p> <p>we</p> <p>qw</p> <p>e</p> <p>qw</p> <p>e</p> <p><img alt="Image title" class="fr-fin fr-dii" src="http://i.froala.com/download/f230c8e0f4dd83433e098c4bafeb3bc9bd12c54c.jpg?1445229186" width="300"></p><p>asdasdasdqweq&nbsp;&nbsp; &nbsp; qweqwe&nbsp; &nbsp; eqweqweqweqeqe&nbsp; &nbsp; e&nbsp; &nbsp; eqeqweqwe</p><p><img alt="Image title" class="fr-fin fr-dii" src = "http://i.froala.com/download/f230c8e0f4dd83433e098c4bafeb3bc9bd12c54c.jpg?1445229123" width= "300"></p> <p><br> </p> <p><br> </p> <p>qw</p> <p>e</p> <p>q</p> <p>e</p> <p>q</p> <p>e</p> <p>qe</p> <p>q</p> <p>rqtqwt<a href="http://qweqweqe" rel="nofollow" target="_blank">qwtqtqtqwtqw</a></p>'; my $regex = qr/<img.*?src\s*=\s*"(.+?)"/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