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 = /^(?!0{3})(?!6{3})[0-8]\d{2}-(?!0{2})\d{2}-(?!0{4})\d{4}$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?!0{3})(?!6{3})[0-8]\\d{2}-(?!0{2})\\d{2}-(?!0{4})\\d{4}$', 'gm') const str = `762-37-6334 429-08-8462 519-75-9429 117-08-6495 544-12-9823 841-01-5655 494-82-9724 568-11-2312 420-42-8078 396-09-7229 869-57-0924 609-44-0934 578-20-1520 835-87-3325 636-03-4578 482-19-1418 364-60-1676 780-23-8549 265-33-9416 221-88-6838 550-13-2720 336-93-2610 193-47-3307 480-82-8373 750-66-0817 122-68-3192 673-84-7164 191-03-8274 412-41-9768 888-21-9775 805-53-9154 150-26-0934 880-42-1378 853-41-1922 467-22-3453 220-91-4157 657-24-3167 229-17-5111 411-38-6337 453-61-4836 123-27-0915 105-56-0050 646-82-7847 105-17-8892 301-70-3833 `; // 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