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

/
/

Test String

Code Generator

Language

Generated Code

const regex = /^(?::\w*:|(?:(\u00a9|\u00ae|[\u2000-\u3300]|\ud83c[\ud000-\udfff]|\ud83d[\ud000-\udfff]|\ud83e[\ud000-\udfff])))\s(?<type>\w*)(?:\((?<scope>.*)\))?!?:\s(?<subject>(?:(?!#).)*(?:(?!\s).))(?:\s\(?(?<ticket>#\d*)\)?)?$/; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?::\\w*:|(?:(\\u00a9|\\u00ae|[\\u2000-\\u3300]|\\ud83c[\\ud000-\\udfff]|\\ud83d[\\ud000-\\udfff]|\\ud83e[\\ud000-\\udfff])))\\s(?<type>\\w*)(?:\\((?<scope>.*)\\))?!?:\\s(?<subject>(?:(?!#).)*(?:(?!\\s).))(?:\\s\\(?(?<ticket>#\\d*)\\)?)?$', '') const str = `✨ feat: add signup pages from (#11) 🧹 feat: add signup pages from (#11) 🐛 feat: add signup pages from (#11) 📝 feat: add signup pages from (#11) 💎 feat: add signup pages from (#11) 📈 feat: add signup pages from (#11) 🧪 feat: add signup pages from (#11) 📦 feat: add signup pages from (#11) ⏪️ feat: add signup pages from (#11) ♻️ feat: add signup pages from (#11) 🏗️ feat: add signup pages from (#11) `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // 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