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 = /(?:[cC][hH]|[lL][lL]|[rR][rR]|[qQ][uU]|[mnñvzsyjhxwMNÑVZSYJHXW]|[fpbtdkgcFPBTDKGC][lrLR]?|[lrLR])?(?:[iuüIUÜ][eaoéáóEAOÉÁÓ][iyuIYU]|[aáAÁ][hH]?[uúUÚ][aáAÁ]|[iuüIUÜ][hH]?[eaoéáóEAOÉÁÓ]|[eaoéáóEAOÉÁÓ][hH]?[iyuIYU]|[iíIÍ][hH]?[uúUÚ]|[uúüUÚÜ][hH]?[iíyIÍY]|[ieaouíéáóúüIEAOUÍÉÁÓÚÜ])(?:(?:(?:(?:[nmNM]|[rR](?![rR]))s?(?![ieaouíéáóúüIEAOUÍÉÁÓÚÜ]))|(?:(?:[mnñvzsyjhxwMNÑVZSYJHXW]|[lL](?![lL]))(?![ieaouíéáóúüIEAOUÍÉÁÓÚÜ]))|(?:(?:[fpbtdkgFPBTDKG]|[cC](?![hH]))(?![lrLR]?[ieaouíéáóúüIEAOUÍÉÁÓÚÜ])))(?!\s|$))?(?:[ndrlsxNDRLSX](?=\s|$))?/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:[cC][hH]|[lL][lL]|[rR][rR]|[qQ][uU]|[mnñvzsyjhxwMNÑVZSYJHXW]|[fpbtdkgcFPBTDKGC][lrLR]?|[lrLR])?(?:[iuüIUÜ][eaoéáóEAOÉÁÓ][iyuIYU]|[aáAÁ][hH]?[uúUÚ][aáAÁ]|[iuüIUÜ][hH]?[eaoéáóEAOÉÁÓ]|[eaoéáóEAOÉÁÓ][hH]?[iyuIYU]|[iíIÍ][hH]?[uúUÚ]|[uúüUÚÜ][hH]?[iíyIÍY]|[ieaouíéáóúüIEAOUÍÉÁÓÚÜ])(?:(?:(?:(?:[nmNM]|[rR](?![rR]))s?(?![ieaouíéáóúüIEAOUÍÉÁÓÚÜ]))|(?:(?:[mnñvzsyjhxwMNÑVZSYJHXW]|[lL](?![lL]))(?![ieaouíéáóúüIEAOUÍÉÁÓÚÜ]))|(?:(?:[fpbtdkgFPBTDKG]|[cC](?![hH]))(?![lrLR]?[ieaouíéáóúüIEAOUÍÉÁÓÚÜ])))(?!\\s|$))?(?:[ndrlsxNDRLSX](?=\\s|$))?', 'gm') const str = `SÍLABA CV casado caro NÚCLEOS VOCÁLICOS DIPTONGOS ai, au, ei, eu, oi, ou, ui, iu, ia, ua, ie, ue, io, uo varió comió diario miel CON DOS CERRADAS distribuido atribuir atribuí muy fui rey pausa tierra ciudad buitre CON H INTERCALADA desahuciar, ahijado TRIPTONGOS santigüeis guay guau rey haliéutica hioides huaico AUA palauano nahuatl cacahuatal HIATOS NORMATIVOS (DOS CONSONANTES ABIERTAS) aorta héroe almohada línea HIATOS tú sabrías, sabías, vosotros sabíais raúl oído búho tío púa ATAQUE C+LÍQUIDA cromo claro cabra triple dígrafos CODAS silbo cansado tacto texto anticiparse álbumes asfixia enloquecer SUCESIÓN NS MS RS transportar transacción torso perspectivas samsara CODAS A FINAL DE PALABRA hablan hablar hablad riel rieles sílex recto DÍGRAFOS chica coche llave calle carro EXTRANJERISMOS pícnic hámster mozzarella marketing búnker sándwich `; // 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