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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

Generated Code

const regex = /^Caín Daniel Romano Sánchez 35 Masculino (Ecuador) San Pablo de Manta./gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^Caín Daniel Romano Sánchez 35 Masculino (Ecuador) San Pablo de Manta.', 'gm') const str = `Caín Daniel Romano Sánchez 35 Masculino Ecuador San Pablo de Manta Darío Cristiano Hernandez Martinez 15 Masculino Bolivia Sacaba Emily Alessia Bianco Sutori 15 Femenino Francia Burdeos Luis Hilario Hamasaki Schneider 57 Masculino Francia Arles Valentin Roberto Rodriguez Rinaldi 43 Masculino Ecuador Santiago de Guayaquil Ruby Olivia Johnson Gutierrez 38 Femenino Bolivia Sucre Khushi Florence López Messina 50 Femenino Francia París Tiburcio Pacifico Feraud Brown 23 Masculino Brasil Rio de Janeiro Carla Martina Santoro Fernandez 9 Femenino Bolivia Guayaramerín Emma Antonella Williams Himura 43 Femenino Ecuador San Pedro de Riobamba `; // 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