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

const regex = /(?<phase>[0-9]+([,|.]?[0-9]+)?)[\t](?<voltage>[0-9]+([,|.]?[0-9]+)?)[\t](?<fault>[0-9]+([,|.]?[0-9]+)?)[\t](?<PD>[0-9]+([,|.]?[0-9]+)?)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<phase>[0-9]+([,|.]?[0-9]+)?)[\\t](?<voltage>[0-9]+([,|.]?[0-9]+)?)[\\t](?<fault>[0-9]+([,|.]?[0-9]+)?)[\\t](?<PD>[0-9]+([,|.]?[0-9]+)?)', 'gm') const 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 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions