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 = /TST(?'TQTId'\d{5})|[ \d]{2}\d\.FV.*(?'IssuingAirline'\w\w)|FARE (?'FarePricingIndicator'.) (?'FareCurrency'...)(?'Fare'.{11})|GRAND TOTAL (?'GTCurrency'...)(?'GrandTotal'.{11})|(?'Seg'[ \d]\d . (?'Origin'\w\w\w) (?'Carrier'..) (?'FlightNo'....) (?'Class'.).(?'DepDate'\d\d\w\w\w).(?'DepTime'\d\d\d\d) (?'Status'...) (?'FareBasis'.{8}) (.{18})(?'BgAllowance'...))|^ (?'Destination'\w\w\w).*$|^.*$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('TST(?\'TQTId\'\\d{5})|[ \\d]{2}\\d\\.FV.*(?\'IssuingAirline\'\\w\\w)|FARE (?\'FarePricingIndicator\'.) (?\'FareCurrency\'...)(?\'Fare\'.{11})|GRAND TOTAL (?\'GTCurrency\'...)(?\'GrandTotal\'.{11})|(?\'Seg\'[ \\d]\\d . (?\'Origin\'\\w\\w\\w) (?\'Carrier\'..) (?\'FlightNo\'....) (?\'Class\'.).(?\'DepDate\'\\d\\d\\w\\w\\w).(?\'DepTime\'\\d\\d\\d\\d) (?\'Status\'...) (?\'FareBasis\'.{8}) (.{18})(?\'BgAllowance\'...))|^ (?\'Destination\'\\w\\w\\w).*$|^.*$', 'gm') const str = `TST00002 ATHG42100 CN/02MAY I 0 LD 24SEP23 2359 OD MNLBRE T- FXP 1.ABAYARE/ROMEO DACER MR(ID7833) 2.SEBASTIAN/JAY AR SIMON MR(ID47129) 1 MNL TK 085 Y 24SEP 2125 OK YFOW 30K 2 X IST TK 1331 Y 25SEP 0720 OK YFOW 30K BRE FARE F USD 2000.00 EQUIV EUR 1810.00 TX001 X EUR 193.60-YRVA TX002 X EUR 8.95-LIDC TX003 X EUR 1.50-M6SE TX004 X EUR 5.00-TRAE TX005 X EUR 0.85-RAAD TOTAL EUR 2019.90 BSR 0.90463353 GRAND TOTAL EUR 2019.90 MNL TK X/IST TK BRE2000.00NUC2000.00END ROE1.000000 18.FE NONEND/TK ONLY 19.FM *F*0.00 20.FP INV 21.FV TK`; // 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