Regular Expressions 101

Save & Manage Regex

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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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'N O 100% WHOLE WHEAT N O BUTTER BREAD N O HONEY WHT N O LIGHT HONEY N O LIGHT WHEAT N O WHITE WHEAT HAMS N O WHITE WHEAT HOTDOGS N. OWN HONEY WHEAT BUN N.O 6CT 100% WHOLE N.O 6CT MULTI GRAIN N.O. 100% W WHEAT N.O. 100% W WHEAT N.O. HEALTHY N.O. Original Bagel 20 OZ N.O. WHITE WHEAT N.O.ALL NATURAL 12 GRAIN N.O.ALL NATURAL WH WHT N/O BUTTER HAMBURGER BUN N/O DOUBLE FIBER WHEAT NAT OWN BTR HOT DOG BUNS NAT OWN CIN RAISIN NAT OWN ENG MUF NAT OWN HNY WHT HD BUNS NAT.OWN ORG HONEY WHEAT NATURE O BREAD 100% WHL WHEAT W/ HONEY 16 OZ NATURES 16 OZ SGRFR WHOL GRN NATURE\'S 2/20Z 100% WHEAT BRD NATURE\'S 2/20Z 100% WHEAT BRD NATURE\'S 2/20Z BUTTER BREAD NATURE\'S 2/20Z BUTTER BREAD NATURE\'S 2/20Z HONEY WHEAT NATURE\'S 2/20Z HONEY WHEAT NATURE\'S 24 OZ DOUBLE FIBER NATURES OWN BUTTER ROLLS NATURES OWN CINNAMON RAIS NATURES OWN HONEY WHEAT THIN 20 OZ NATURES OWN HONY 7 GRAIN NATURES OWN LIFE 7 GRAINS NATURES OWN LIFE WHEAT & PROTEIN BREAD NO 100% W G WHEAT BREAD NO 100% WHL GRN OVAL NO ALL NAT HNY WHT BRY NO SGR FRE WHOLE GRAIN NO WHITE/WHEAT ROUND TOP NTRS OWN HNY OAT SOFT NTRS OWN HOTS NTRS OWN HOTS'; my $regex = qr/^((NA?TU?RE?S?\s?OWN\b)|(NAT\s?\.?OWN\b)|(N\s?\W?\.?O\.?\b)|(N\.\sOWN\b)|(NATURE\W?S\b)|(NATURE\sO\b))/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