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 = /^[Uu]\w{0,10}\s*[Mm]*\w{0,4}(\,)*\s*[Rr]*\w{0,3}\s*\w{0,1}\s*[Pp]*\w{0,9}\s\w{0,2}\s*[Ss]\w{0,2}\s*[Ff]\w{0,8}\s*[Xx]\w{0,5}\s*\w{0,2}\s*[Cc]*\w{0,9}/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^[Uu]\\w{0,10}\\s*[Mm]*\\w{0,4}(\\,)*\\s*[Rr]*\\w{0,3}\\s*\\w{0,1}\\s*[Pp]*\\w{0,9}\\s\\w{0,2}\\s*[Ss]\\w{0,2}\\s*[Ff]\\w{0,8}\\s*[Xx]\\w{0,5}\\s*\\w{0,2}\\s*[Cc]*\\w{0,9}', 'gm') const str = `Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca universidad mayor, real y pontificia de san francisco xavier de chuquisaca USFX usfx Universidad San Francisco Xavier `; // 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