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

/
/
gim

Test String

Code Generator

Generated Code

const regex = /(?<!x)(\d{9}|\d{3}-\d{6}|\d{3}-\d{3}-\d{3})/gim; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<!x)(\\d{9}|\\d{3}-\\d{6}|\\d{3}-\\d{3}-\\d{3})', 'gim') const str = `//Use cases that are working with the above regex. x123456789 X123456789 x123-456-789 X123-456-789 123-456-789 ordernumber123-456-789 order number123-456789 order number 123456789 123-456789 123456789 ordernumber-x123456787 ordernumber-123456787 ordernumber - 123456789 ordernumber #123456789 ordernumber *anysplcharacter*123456789 ordernumber !@#\$%^&123456789 123456789*@*#123456789 social security number 123-456-789 ordernumber !@#\$%^&x123456789 123456789 #@%#\$%#\$123456789#\$%#\$^\$# // Use cases that are not working with the above regex. Need to modify the regex 123456789 123 45 6789 123-45-6789 123-45-6789 123 – 45 – 6789 123.45.6789 123_45_6789 123 456 789 123-456-789 123 – 456 – 789 123.456.789 123_456_789 1234 56 789 1234-56-789 1234 – 56 – 789 1234.56.789 1234_56_789 12 345 6789 12-345-6789 12 – 345 – 6789 12.345.6789 12_345_6789`; // 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