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 = 'DOA000281_ICS_U-M1-1740_R-M1-1740_W.TAB DOA000281_ICS_U-M1-1740_R-M200-1740CCU_W.TAB DOA000281_ICS_U-M1-1740_R-M200-1740_W.TAB DOA000281_ICS_U-M1-1740_R-M30-1740CCU_W.TAB DOA000281_ICS_U-M1-300_R-M1-300_S.TAB DOA000281_ICS_U-M1-300_R-M200-300CCU_S.TAB DOA000281_ICS_U-M1-300_R-M200-300_S.TAB DOA000281_ICS_U-M1-300_R-M30-300CCU_S.TAB DOA000281_ICS_U-M10-1740_R-M10-1740_W.TAB DOA000281_ICS_U-M10-300_R-M10-300_S.TAB DOA000281_ICS_U-M2-1740_R-M2-1740_W.TAB DOA000281_ICS_U-M2-300_R-M2-300_S.TAB DOA000281_ICS_U-M200-1740CCU_R-M1-1740_W.TAB DOA000281_ICS_U-M200-1740_R-M1-1740_W.TAB DOA000281_ICS_U-M200-300CCU_R-M1-300_S.TAB DOA000281_ICS_U-M200-300_R-M1-300_S.TAB DOA000281_ICS_U-M30-1740CCU_R-M1-1740_W.TAB DOA000281_ICS_U-M30-300CCU_R-M1-300_S.TAB DOA000281_ICS_U-M5-1740_R-M5-1740_W.TAB DOA000281_ICS_U-M5-1740_R-M50-1740_W.TAB DOA000281_ICS_U-M5-300_R-M5-300_S.TAB DOA000281_ICS_U-M5-300_R-M50-300_S.TAB DOA000281_ICS_U-M50-1740_R-M5-1740_W.TAB DOA000281_ICS_U-M50-300_R-M5-300_S.TAB DOA_000533_ICS_10y180sMax.tab DOA_000533_ICS_10y360wMax.tab DOA_000533_ICS_1y180sMax.tab DOA_000533_ICS_1y180s_200ccy180sMax.tab DOA_000533_ICS_1y180s_200y180sMax.tab DOA_000533_ICS_1y180s_30ccy180sMax.tab DOA_000533_ICS_1y360wMax.tab DOA_000533_ICS_1y360w_200ccy360wMax.tab DOA_000533_ICS_1y360w_200y360wMax.tab DOA_000533_ICS_1y360w_30ccy360wMax.tab DOA_000533_ICS_200ccy180s_1y180sMax.tab DOA_000533_ICS_200ccy360w_1y360wMax.tab DOA_000533_ICS_200y180s_1y180sMax.tab DOA_000533_ICS_200y360w_1y360wMax.tab DOA_000533_ICS_2y180sMax.tab DOA_000533_ICS_2y360wMax.tab DOA_000533_ICS_30ccy180s_1y180sMax.tab DOA_000533_ICS_30ccy360w_1y360wMax.tab DOA_000533_ICS_50y180s_5y180sMax.tab DOA_000533_ICS_50y360w_5y360wMax.tab DOA_000533_ICS_5y180sMax.tab DOA_000533_ICS_5y180s_50y180sMax.tab DOA_000533_ICS_5y360wMax.tab DOA_000533_ICS_5y360w_50y360wMax.tab CFA_AUG2018_2D DOA_000537_ICS_10y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_10y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600s_200ccy600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600s_200y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600s_30ccy600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600w_200ccy600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600w_200y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600w_30ccy600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200ccy600s_1y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200ccy600w_1y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200y600s_1y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200y600w_1y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_2y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_2y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_30ccy600s_1y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_30ccy600w_1y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_50y600s_5y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_50y600w_5y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_5y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_5y600s_50y600sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_5y600wMax.TAB CFA_AUG2018_2D DOA_000537_ICS_5y600w_50y600wMax.TAB DOA000557_ICS_U-M1-300_R-M1-300_W_2D.TAB DOA000557_ICS_U-M1-300_R-M200-300CCU_W_2D.TAB DOA000557_ICS_U-M1-300_R-M200-300_W_2D.TAB DOA000557_ICS_U-M1-300_R-M30-300CCU_W_2D.TAB DOA000557_ICS_U-M1-60_R-M1-60_S_2D.TAB DOA000557_ICS_U-M1-60_R-M200-60CCU_S_2D.TAB DOA000557_ICS_U-M1-60_R-M200-60_S_2D.TAB DOA000557_ICS_U-M1-60_R-M30-60CCU_S_2D.TAB DOA000557_ICS_U-M10-300_R-M10-300_W_2D.TAB DOA000557_ICS_U-M10-60_R-M10-60_S_2D.TAB DOA000557_ICS_U-M2-300_R-M2-300_W_2D.TAB DOA000557_ICS_U-M2-60_R-M2-60_S_2D.TAB DOA000557_ICS_U-M200-300CCU_R-M1-300_W_2D.TAB DOA000557_ICS_U-M200-300_R-M1-300_W_2D.TAB DOA000557_ICS_U-M200-60CCU_R-M1-60_S_2D.TAB DOA000557_ICS_U-M200-60_R-M1-60_S_2D.TAB DOA000557_ICS_U-M30-300CCU_R-M1-300_W_2D.TAB DOA000557_ICS_U-M30-60CCU_R-M1-60_S_2D.TAB DOA000557_ICS_U-M5-300_R-M5-300_W_2D.TAB DOA000557_ICS_U-M5-300_R-M50-300_W_2D.TAB DOA000557_ICS_U-M5-60_R-M5-60_S_2D.TAB DOA000557_ICS_U-M5-60_R-M50-60_S_2D.TAB DOA000557_ICS_U-M50-300_R-M5-300_W_2D.TAB DOA000557_ICS_U-M50-60_R-M5-60_S_2D.TAB DOA000616_617 ICS U-M1-300_R-M1-300_Winter.TAB DOA000616_617 ICS U-M1-300_R-M200-300CCU_Winter.TAB DOA000616_617 ICS U-M1-300_R-M200-300_Winter.TAB DOA000616_617 ICS U-M1-300_R-M30-300CCU_Winter.TAB DOA000616_617 ICS U-M1-60_R-M1-60_Summer.TAB DOA000616_617 ICS U-M1-60_R-M200-60CCU_Summer.TAB DOA000616_617 ICS U-M1-60_R-M200-60_Summer.TAB DOA000616_617 ICS U-M1-60_R-M30-60CCU_Summer.TAB DOA000616_617 ICS U-M10-300_R-M10-300_Winter.TAB DOA000616_617 ICS U-M10-60_R-M10-60_Summer.TAB DOA000616_617 ICS U-M2-300_R-M2-300_Winter.TAB DOA000616_617 ICS U-M2-60_R-M2-60_Summer.TAB DOA000616_617 ICS U-M200-300CCU_R-M1-300_Winter.TAB DOA000616_617 ICS U-M200-300_R-M1-300_Winter.TAB DOA000616_617 ICS U-M200-60CCU_R-M1-60_Summer.TAB DOA000616_617 ICS U-M200-60_R-M1-60_Summer.TAB DOA000616_617 ICS U-M30-300CCU_R-M1-300_Winter.TAB DOA000616_617 ICS U-M30-60CCU_R-M1-60_Summer.TAB DOA000616_617 ICS U-M5-300_R-M5-300_Winter.TAB DOA000616_617 ICS U-M5-300_R-M50-300_Winter.TAB DOA000616_617 ICS U-M5-60_R-M5-60_Summer.TAB DOA000616_617 ICS U-M5-60_R-M50-60_Summer.TAB DOA000616_617 ICS U-M50-300_R-M5-300_Winter.TAB DOA000616_617 ICS U-M50-60_R-M5-60_Summer.TAB DOA000674_ICS_U_M10_120_R_M10_120_S.TAB DOA000674_ICS_U_M10_600_R_M10_600_W.TAB DOA000674_ICS_U_M1_120_R_M1_120_S.TAB DOA000674_ICS_U_M1_120_R_M200_120CCU_S.TAB DOA000674_ICS_U_M1_120_R_M200_120_S.TAB DOA000674_ICS_U_M1_120_R_M30_120CCU_S.TAB DOA000674_ICS_U_M1_600_R_M1_600_W.TAB DOA000674_ICS_U_M1_600_R_M200_600CCU_W.TAB DOA000674_ICS_U_M1_600_R_M200_600_W.TAB DOA000674_ICS_U_M1_600_R_M30_600CCU_W.TAB DOA000674_ICS_U_M200_120CCU_R_M1_120_S.TAB DOA000674_ICS_U_M200_120_R_M1_120_S.TAB DOA000674_ICS_U_M200_600CCU_R_M1_600_W.TAB DOA000674_ICS_U_M200_600_R_M1_600_W.TAB DOA000674_ICS_U_M2_120_R_M2_120_S.TAB DOA000674_ICS_U_M2_600_R_M2_600_W.TAB DOA000674_ICS_U_M30_120CCU_R_M1_120_S.TAB DOA000674_ICS_U_M30_600CCU_R_M1_600_W.TAB DOA000674_ICS_U_M50_120_R_M5_120_S.TAB DOA000674_ICS_U_M50_600_R_M5_600_W.TAB DOA000674_ICS_U_M5_120_R_M50_120_S.TAB DOA000674_ICS_U_M5_120_R_M5_120_S.TAB DOA000674_ICS_U_M5_600_R_M50_600_W.TAB DOA000674_ICS_U_M5_600_R_M5_600_W.TAB DOA002372_ICS_U_M10_120_R_M10_120_S_2D.TAB DOA002372_ICS_U_M10_600_R_M10_600_W_2D.TAB DOA002372_ICS_U_M1_120_R_M1_120_S_2D.TAB DOA002372_ICS_U_M1_120_R_M200_120CC_S_2D.TAB DOA002372_ICS_U_M1_120_R_M200_120_S_2D.TAB DOA002372_ICS_U_M1_120_R_M30_120CC_S_2D.TAB DOA002372_ICS_U_M1_600_R_M1_600_W_2D.TAB DOA002372_ICS_U_M1_600_R_M200_600CC_W_2D.TAB DOA002372_ICS_U_M1_600_R_M200_600_W_2D.TAB DOA002372_ICS_U_M1_600_R_M30_600CC_W_2D.TAB DOA002372_ICS_U_M200_120CC_R_M1_120_S_2D.TAB DOA002372_ICS_U_M200_120_R_M1_120_S_2D.TAB DOA002372_ICS_U_M200_600CC_R_M1_600_W_2D.TAB DOA002372_ICS_U_M200_600_R_M1_600_W_2D.TAB DOA002372_ICS_U_M2_120_R_M2_120_S_2D.TAB DOA002372_ICS_U_M2_600_R_M2_600_W_2D.TAB DOA002372_ICS_U_M30_120CC_R_M1_120_S_2D.TAB DOA002372_ICS_U_M30_600CC_R_M1_600_W_2D.TAB DOA002372_ICS_U_M50_120_R_M5_120_S_2D.TAB DOA002372_ICS_U_M50_600_R_M5_600_W_2D.TAB DOA002372_ICS_U_M5_120_R_M50_120_S_2D.TAB DOA002372_ICS_U_M5_120_R_M5_120_S_2D.TAB DOA002372_ICS_U_M5_600_R_M50_600_W_2D.TAB DOA002372_ICS_U_M5_600_R_M5_600_W_2D.TAB '; my $regex = qr/(\d{1,3})(cc|)y\d{1,4}\w(?:[-_](\d{1,3})(cc|)y)?/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