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 = /(Gen|Gn|Ex|Lev|Lv|Nm|Dt|Jos|Jue|1°Sam|2°Sam|1°Rey|2°Rey|Job|Sal|Prov|Cant|Is|Jer|Ez|Dan|Dn|Os|Miq|Sof|Zac|Mal|Mt|Mc|Lc|Jn|Hch|Rm|Rom|1°Co|1°Cor|Cor|2°Co|2°Cor|Ga|Gal|Ef|Flp|Col|1°Tes|2°Tes|1°Tim|2°Tim|Tito|Heb|Sant|Stgo|1°Ped|2°Ped|1°Jn|Ap|Tob|Sab|Eclo|Sir|1°Mac|2°Mac|Isaías|Jeremías|Zacarías|Hechos|Mateo|Salmo|Judit) ([0-9]{1,3})(?:,(\d{1,3}))?/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(Gen|Gn|Ex|Lev|Lv|Nm|Dt|Jos|Jue|1°Sam|2°Sam|1°Rey|2°Rey|Job|Sal|Prov|Cant|Is|Jer|Ez|Dan|Dn|Os|Miq|Sof|Zac|Mal|Mt|Mc|Lc|Jn|Hch|Rm|Rom|1°Co|1°Cor|Cor|2°Co|2°Cor|Ga|Gal|Ef|Flp|Col|1°Tes|2°Tes|1°Tim|2°Tim|Tito|Heb|Sant|Stgo|1°Ped|2°Ped|1°Jn|Ap|Tob|Sab|Eclo|Sir|1°Mac|2°Mac|Isaías|Jeremías|Zacarías|Hechos|Mateo|Salmo|Judit) ([0-9]{1,3})(?:,(\\d{1,3}))?', 'gm') const str = `Ex 32,1-14 Rom 1,18ss, (DH 3004 Rom 1,18-2 Ex 32,1-1 Sal 14,1 Heb 11,1: “La fe es Heb 1,1ss Ef 1,9 1°Cor 2,6-10 Heb 11,1: Heb 12,2, se exalta a 1°Cor 15,3-5 y Hch 2,22-24. Mt 25,40; Stgo 2,14-26; 1°Jn 4,8.20 Gen 31,5, Gen 31,42, etc. Gen 45,8. o SEB Ex 20,5-6; Ex 34,6 Ex 22 `; // 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