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 = /((?:\+|00)[17](?: |\-|\.)?|(?:\+|00)[1-9]\d{0,2}(?: |\-|\.)?|(?:\+|00)1\-\d{3}(?: |\-|\.)?)?(0\d|\([0-9]{3}\)|[1-9]{0,3})(?:((?: |\-|\.)[0-9]{2}){4}|((?:[0-9]{2}){4})|((?: |\-|\.)[0-9]{3}(?: |\-|\.)[0-9]{4})|([0-9]{7}))/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('((?:\\+|00)[17](?: |\\-|\\.)?|(?:\\+|00)[1-9]\\d{0,2}(?: |\\-|\\.)?|(?:\\+|00)1\\-\\d{3}(?: |\\-|\\.)?)?(0\\d|\\([0-9]{3}\\)|[1-9]{0,3})(?:((?: |\\-|\\.)[0-9]{2}){4}|((?:[0-9]{2}){4})|((?: |\\-|\\.)[0-9]{3}(?: |\\-|\\.)[0-9]{4})|([0-9]{7}))', 'g') const str = ` 12345678901 12345678901x1234 345678901x1234 12344678901 12345678901 12345678901 12345678901 +4112345678 +441234567890 1 (234) 567-8901 1 (234) 567-8901 x1234 01 23 45 56 78 335.23.23.23.23 0689912549 +33698912549 +33 6 79 91 25 49 +33-6-79-91-25-49 (555)-555-5555 555-555-5555 +1-238 6 79 91 25 49 +1-555-532-3455 +15555323455 55555555555555555555555555 +7 06 79 91 25 49 935 263223 64 949 067 9 91 254 9 331 23 45 56 78 331.23.45.56.78 331 23 45 56.78 33123455678 2312523125 `; // 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