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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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 = new RegExp('^(?:[\\uD83C\\uDF00-\\uD83D\\uDDFF]|[\\uD83E\\uDD00-\\uD83E\\uDDFF]|[\\uD83D\\uDE00-\\uD83D\\uDE4F]|[\\uD83D\\uDE80-\\uD83D\\uDEFF]|[\\u2600-\\u26FF]\\uFE0F?|[\\u2700-\\u27BF]\\uFE0F?|\\u24C2\\uFE0F?|[\\uD83C\\uDDE6-\\uD83C\\uDDFF]{1,2}|[\\uD83C\\uDD70\\uD83C\\uDD71\\uD83C\\uDD7E\\uD83C\\uDD7F\\uD83C\\uDD8E\\uD83C\\uDD91-\\uD83C\\uDD9A]\\uFE0F?|[\\u0023\\u002A\\u0030-\\u0039]\\uFE0F?\\u20E3|[\\u2194-\\u2199\\u21A9-\\u21AA]\\uFE0F?|[\\u2B05-\\u2B07\\u2B1B\\u2B1C\\u2B50\\u2B55]\\uFE0F?|[\\u2934\\u2935]\\uFE0F?|[\\u3030\\u303D]\\uFE0F?|[\\u3297\\u3299]\\uFE0F?|[\\uD83C\\uDE01\\uD83C\\uDE02\\uD83C\\uDE1A\\uD83C\\uDE2F\\uD83C\\uDE32-\\uD83C\\uDE3A\\uD83C\\uDE50\\uD83C\\uDE51]\\uFE0F?|[\\u203C\\u2049]\\uFE0F?|[\\u25AA\\u25AB\\u25B6\\u25C0\\u25FB-\\u25FE]\\uFE0F?|[\\u00A9\\u00AE]\\uFE0F?|[\\u2122\\u2139]\\uFE0F?|\\uD83C\\uDC04\\uFE0F?|\\uD83C\\uDCCF\\uFE0F?|[\\u231A\\u231B\\u2328\\u23CF\\u23E9-\\u23F3\\u23F8-\\u23FA]\\uFE0F?)+$', 'gm') const str = `🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼🇿🇼abc`; // 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