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 = /(?<=m)(2|3)/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<=m)(2|3)', 'g') const str = `superscript (?<=m)(2|3) ®|™ (?<=\\d)(de|ème) REF \\d{6}/(D|T|X) REF2 \\d{3}/(D|T|X) REF3 \\d{6}(?-) VET garantie[^\\r\\n]+jaar Fraction \\b1/2\\b PARQUET STRATIFIE ‘MEGALOFT’ Différents motifs Longueur 1286mm x largeur 194mm 10000kcal/u 25mm2 10dm3 10dm3/u 1000m3/u 850l/u 1000m3/h 850l/h 1,99m2/pak 1,33m3 1,25m2 25kg 700559/D 1,59m3/pak 1,996m2/paquet 700496-123566-123/D 1,996m2/paquet 123566-123/D 1,99m2 en 199m3/h 135234-123/D Gerst 004729/D Schors 058157/D Ø 30/60 x H230cm Polyester doek 280gr/m2 Crossover®-ontstekingssysteem ™ Toelatingsnr: 3001B 32/38mm slang ZANDFILTERKIT 10m3/u Debiet 1,2m2/u Zinklaag: 180-250gr/m2 2de handgreep 2ème poignon Garantie 25 jaar 10 jaar waarborg Maaihoogteregeling 20-75mm Gerst 004729/D Schors 058157/D Ø 30/60 x H230cm Polyester doek 280gr/m2 Crossover®-ontstekingssysteem ™ Toelatingsnr: 3001B 32/38mm slang ZANDFILTERKIT 10m3/u Debiet 1,2m2/u Zinklaag: 180-250gr/m2 2de handgreep 2ème poignon garantie 25 jaar garantie 25 jaar Garantie 25 ans jar Jaar Garantie 25 25 jaar garantie 10 jaar waarborg Maaihoogteregeling 20-75mm 1/2 ® 541358/9/60 541358-12-12/D 541358-123-123/D 541358-1234-1234/D 541358-12345-12345/D 541358-123456-123456/D`; // 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