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

/
/
gmu

Test String

Code Generator

Language

Generated Code

const regex = /(^(?<date>\d{1,2}\/\d{1,2}\/\d{1,2}),\s(?<time>\d{1,2}:\d{1,2})\s-\s(?<user>.*?):\s)|(?<word>\w+(?:\'\w+)?|[\x{1F600}-\x{1F64F}]|[\x{1F300}-\x{1F5FF}]|[\x{1F680}-\x{1F6FF}]|[\x{2600}-\x{26FF}]|[\x{2700}-\x{27BF}]|[^\w\s~"!@#$%*()_+-=¹²³§ªº`^{}[\]<>,.;:?\/\\\|\n\r\t])/gmu; // Alternative syntax using RegExp constructor // const regex = new RegExp('(^(?<date>\\d{1,2}\\\/\\d{1,2}\\\/\\d{1,2}),\\s(?<time>\\d{1,2}:\\d{1,2})\\s-\\s(?<user>.*?):\\s)|(?<word>\\w+(?:\\\'\\w+)?|[\\x{1F600}-\\x{1F64F}]|[\\x{1F300}-\\x{1F5FF}]|[\\x{1F680}-\\x{1F6FF}]|[\\x{2600}-\\x{26FF}]|[\\x{2700}-\\x{27BF}]|[^\\w\\s~"!@#$%*()_+-=¹²³§ªº`^{}[\\]<>,.;:?\\\/\\\\\\|\\n\\r\\t])', 'gmu') const str = `3/30/20, 17:06 - Me: Hi brow! I need to test some regex. 3/30/20, 17:06 - John Doe: 👍👍👍 Let's do it! 3/30/20, 17:08 - Me: ⚡️🦄🧀🏀🤪🎺🎪💾🚽📎💕💯✅ 🇯🇵 🕔➡️👶🚴👌👽 3/30/20, 17:10 - Someone: 🐵🙈🙉🙊🐒 We're talking emoji language? https://regex101.com/library`; // 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