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

r"
"
gm

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('\\(?(((((([hH]?[tT]?)|[fF]?)[tT]?[pP]?s?:?)?(\\/\\/)?|[A-Za-z]+|(\\/\\/)?)?[A-Za-z]+)\\.\\S+(\\/|\\.|#)\\S+)(?!(\\.com))\\)?', 'gm') const str = `DONT MATCH \$200.00/month... for positioningacceleratorprogram.com on youtube.com eeeee https://www. //www. or not def//: :google.com ://google.com google.com or ld/2018/01/02/mountains-u-s-recycling-pile-up-china-restricts-imports/995134001/ atis:theexpertiseincubator.simplecast.fm/ This MATCH www.google.com https://wWw.csis.org http://youtu.be/abS#PS9 hotshot.io#hash htTps://buFf.ly/2as34vz/MN https://www.usatoday.com/story/news/wor www.asas.io doggie.io/x doggie.io#taggie usatoday.com/story/news/world/2018/01/02/mountains-u-s-recycling-pile-up-china-restricts-imports/995134001/ https://www.google.com http://www.google.com www.google.com htt://www.google.com ://www.google.com here: forms.gle/7j6rFkUjbKXr2skC6 A few again: forms.gle/7j6rFkUjbKXr2skC6 -P (yet): www.acrecoffee.com/shop coffee (nmpinoncoffee.com/products/Traditional%20Piñon?category=coffee0) and (Readin' time: 33 seconds) This is interesting: www.cnbc.com/2019/04/26/the-15-us-jobs-disappearing-the-fastest.html Not of this htfps:theexpertiseincubator.simplecast.fm/ This httPs:theexpertiseincubator.simplecast.fm/ This Life: https://www.thisamericanlife.org/7/quitting Frequency, audience: offlinepodcast.rocks/paid-acquisitions (the setup) offlinepodcast.rocks/podcast-listeners (the payoff). `; // 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