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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /"[^"]*"|\S+/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('"[^"]*"|\\S+', 'g') const str = `2018-04-16T08:09:27.203Z cae70dd2-414c-11e8-836a-354cb4985a41 https 2018-04-15T01:20:31.092381Z app/MBM-L-Publi-V9D386A91UNR/4695f2e72859f540 128.121.50.133:59367 10.0.1.14:80 0.001 0.003 0.000 200 200 934 282 "GET https://www.domain.tld:443/__utm.gif?v=1&_v=j66&a=1866784098&t=pageview&_s=1&dl=https%3A%2F%2Fwww.domain.tld%2Fnews%2Farchived%2Fresources-archived%22001-11%2F&ul=en-us&de=UTF-8&dt=Racal%20reborn%20after%20Thales%20buyout&sd=24-bit&sr=412x732&vp=404x732&je=0&cid=1296878891.1495497600&_gid=1908154735.1495497600&_r=1&z=821631926 HTTP/1.1" "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)" ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 arn:aws:elasticloadbalancing:eu-west-2:123456789012:targetgroup/MBM-L-Cache-1LH0DNU489D55/167e4810f75804c3 "Root=1-5ad2a8df-021aaad5031047e7dec3f2fa" "www.domain.tld" "arn:aws:acm:eu-west-2:123456789012:certificate/1140cbb2-4d4f-44b0-a4d9-a79329c5e361" 0`; // 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