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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /(\d+)\s+(\w{2})\s*(\w{2,5})\s+(\w{5})(?:\s+|\s+(.)\s+)(\w{3})(\w{3})(?:\s+|(?:\s|\*)(\w{3})\s+)(\w{4,5})\s+(\w{4,5})(?:\s+(\w{5}))?.*(?:\n|$)??((?:.|\n)*?)(\n\s*\n)?(?=\d+\s+\w{2}\s*\w{2,5}\s+\w{5}(?:\s+|\s+.\s+)\w{3}\w{3}(?:\s+|(?:\s|\*)\w{3}\s+)\w{4,5}\s+\w{4,5}(?:\s+\w{5})?|$)/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(\\d+)\\s+(\\w{2})\\s*(\\w{2,5})\\s+(\\w{5})(?:\\s+|\\s+(.)\\s+)(\\w{3})(\\w{3})(?:\\s+|(?:\\s|\\*)(\\w{3})\\s+)(\\w{4,5})\\s+(\\w{4,5})(?:\\s+(\\w{5}))?.*(?:\\n|$)??((?:.|\\n)*?)(\\n\\s*\\n)?(?=\\d+\\s+\\w{2}\\s*\\w{2,5}\\s+\\w{5}(?:\\s+|\\s+.\\s+)\\w{3}\\w{3}(?:\\s+|(?:\\s|\\*)\\w{3}\\s+)\\w{4,5}\\s+\\w{4,5}(?:\\s+\\w{5})?|$)', 'g') const str = ` 1 UA 990J 28OCT SFOCDG 340P 1015A 29OCT greg 2 AF1830J 31OCT CDGMXP 900A 1025A 31OCT OPERATED BY AIR CANADA YYZ CHECK-IN WITH AIR CANADA 3 LH 259J 03NOV T MXPFRA 740A 900A 03NOV OPERATED BY LUFTHANSA MAD CHECK-IN WITH LUFTHANSA 4 DL2252Z 01OCT T SATDTW*SS1 1246P 454P 5 DL 98Z 01OCT T DTWCDG*SS1 608P 805A 02OCT W /DCDL /E 6 DL8322Z 02OCT W CDGBOD*SS1 935A 1050A /DCDL /E OPERATED BY AIR FRANCE grggf rge 7 DL9365Z 09OCT W BODAMS*SS1 1150A 140P /DCDL /E OPERATED BY KLM ROYAL DUTCH AIRLINES 8 DL8178Z 09OCT W AMSSLC*SS1 500P 655P /DCDL /E OPERATED BY KLM ROYAL DUTCH AIRLINES fre f 10 LH 454J 03NOV FRASFO 1005A 205P 03NOV 11 LH 454J 03NOV SFOKIV 205P 235P 03NOV`; // 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