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

/
/
gu

Test String

Code Generator

Language

Generated Code

const regex = /[\u{1f300}-\u{1f5ff}\u{1f900}-\u{1f9ff}\u{1f600}-\u{1f64f}\u{1f680}-\u{1f6ff}\u{2600}-\u{26ff}\u{2700}-\u{27bf}\u{1f1e6}-\u{1f1ff}\u{1f191}-\u{1f251}\u{1f004}\u{1f0cf}\u{1f170}-\u{1f171}\u{1f17e}-\u{1f17f}\u{1f18e}\u{3030}\u{2b50}\u{2b55}\u{2934}-\u{2935}\u{2b05}-\u{2b07}\u{2b1b}-\u{2b1c}\u{3297}\u{3299}\u{303d}\u{00a9}\u{00ae}\u{2122}\u{23f3}\u{24c2}\u{23e9}-\u{23ef}\u{25b6}\u{23f8}-\u{23fa}]/gu; // Alternative syntax using RegExp constructor // const regex = new RegExp('[\\u{1f300}-\\u{1f5ff}\\u{1f900}-\\u{1f9ff}\\u{1f600}-\\u{1f64f}\\u{1f680}-\\u{1f6ff}\\u{2600}-\\u{26ff}\\u{2700}-\\u{27bf}\\u{1f1e6}-\\u{1f1ff}\\u{1f191}-\\u{1f251}\\u{1f004}\\u{1f0cf}\\u{1f170}-\\u{1f171}\\u{1f17e}-\\u{1f17f}\\u{1f18e}\\u{3030}\\u{2b50}\\u{2b55}\\u{2934}-\\u{2935}\\u{2b05}-\\u{2b07}\\u{2b1b}-\\u{2b1c}\\u{3297}\\u{3299}\\u{303d}\\u{00a9}\\u{00ae}\\u{2122}\\u{23f3}\\u{24c2}\\u{23e9}-\\u{23ef}\\u{25b6}\\u{23f8}-\\u{23fa}]', 'gu') const str = `🌍💰🕧👨👩👧🤔🈂ī¸ 😘 ☃♨ī¸đŸ—ēī¸đŸ“„đŸĨ⚒ī¸đŸŒ€đŸĻđŸˆˇī¸đŸˆĩ🆚🀄⭐ī¸â¤ī¸âžĄī¸âž°ī¸â¤´ī¸âžŋī¸â­•ī¸ãŠ™ī¸đŸ€„đŸƒđŸ…ąī¸đŸ†Žã€°ī¸â¤ĩī¸âŦœī¸ã€Ŋī¸â­ī¸đŸ†’⏊ī¸ÂŠī¸â“‚ī¸â˜Ēī¸â˜•ī¸âēī¸â–ļī¸ÂŽī¸â„ĸī¸âŗī¸`; // 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