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 = 'Fault location: Cable-length (m): 266 Phase Voltage(kV) Fault(m): PD (pC): 1 11.0 141.452 142.857 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_11kV_2016-08-17-11\'04\'05.loc 1 11.0 141.452 190.476 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_11kV_2016-08-17-11\'04\'19.loc 1 11.0 141.452 161.905 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_11kV_2016-08-17-11\'04\'19.loc 1 11.0 139.673 171.429 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_11kV_2016-08-17-11\'04\'33.loc 1 11.0 141.452 152.381 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_11kV_2016-08-17-11\'04\'33.loc 1 13.0 140.562 295.238 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'34.loc 1 13.0 137.004 285.714 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'34.loc 1 13.0 140.562 238.095 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'34.loc 1 13.0 142.341 200.000 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'34.loc 1 13.0 140.562 333.333 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'50.loc 1 13.0 139.673 314.286 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'50.loc 3 13.0 136.114 228.571 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'39.loc 1 13.0 136.114 171.429 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'50.loc 1 13.0 141.452 276.190 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'06\'06.loc 1 13.0 139.673 180.952 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'06\'06.loc 2 9.0 141.452 142.857 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_9kV_2016-08-17-11\'08\'58.loc 2 11.0 136.114 304.762 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'13.loc 2 11.0 140.562 209.524 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'13.loc 2 11.0 138.783 285.714 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'30.loc 2 11.0 140.562 219.048 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'30.loc 2 11.0 139.673 333.333 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'45.loc 2 11.0 137.004 238.095 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_11kV_2016-08-17-11\'09\'45.loc 2 13.0 140.562 447.619 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'00.loc 2 13.0 139.673 352.381 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'00.loc 2 13.0 137.893 323.810 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'00.loc 2 13.0 134.335 171.429 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'00.loc 2 13.0 140.562 447.619 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'16.loc 2 13.0 140.562 419.048 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'16.loc 2 13.0 138.783 390.476 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'16.loc 2 13.0 138.783 304.762 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'16.loc 2 13.0 140.562 200.000 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'16.loc 2 13.0 140.562 447.619 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'41.loc 2 13.0 138.783 409.524 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'41.loc 2 13.0 139.673 361.905 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'41.loc 2 13.0 137.893 352.381 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L2_13kV_2016-08-17-11\'10\'41.loc 3 9.0 139.673 142.857 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_9kV_2016-08-17-11\'13\'10.loc 3 11.0 120.101 342.857 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'27.loc 3 11.0 137.893 171.429 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'27.loc 3 11.0 139.673 219.048 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'43.loc 3 11.0 139.673 190.476 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'43.loc 3 11.0 139.673 304.762 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'57.loc 3 11.0 139.673 161.905 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_11kV_2016-08-17-11\'13\'57.loc 3 13.0 137.893 380.952 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'11.loc 3 13.0 140.562 352.381 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'11.loc 3 13.0 139.673 352.381 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'11.loc 3 13.0 137.893 333.333 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'11.loc 3 13.0 140.562 200.000 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'11.loc 3 13.0 139.673 428.571 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'25.loc 3 13.0 140.562 409.524 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'25.loc 3 13.0 137.004 323.810 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'25.loc 3 13.0 136.114 209.524 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'25.loc 3 13.0 120.101 628.571 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'39.loc 3 13.0 140.562 314.286 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'39.loc 3 13.0 137.893 266.667 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L3_13kV_2016-08-17-11\'14\'39.loc 1 13.0 139.673 238.095 C:\\Users\\z2066\\Documents\\Munka\\Diagnosztika\\KD 2016\\OWTS\\Gyor regio\\Sopron\\Frankenburg BHTR-Kossuth KTW\\L1_13kV_2016-08-17-11\'05\'50.loc Joints: 0 266 '; my $regex = qr/(?<phase>[0-9]+([,|.]?[0-9]+)?)[\t](?<voltage>[0-9]+([,|.]?[0-9]+)?)[\t](?<fault>[0-9]+([,|.]?[0-9]+)?)[\t](?<PD>[0-9]+([,|.]?[0-9]+)?)/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