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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /([\w+]+\:\/\/)?([\w\d-]+\.)*[\w-]+[\(\)\#\.\:]\w+([\(\)\/\?\=\&\#\.]?[\w-]+)*\/?[\(\-\w\)\?\=\#_]*/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('([\\w+]+\\:\\\/\\\/)?([\\w\\d-]+\\.)*[\\w-]+[\\(\\)\\#\\.\\:]\\w+([\\(\\)\\\/\\?\\=\\&\\#\\.]?[\\w-]+)*\\\/?[\\(\\-\\w\\)\\?\\=\\#_]*', 'gm') const str = `https://daringfireball.net/2010/07/improved_regex_for_matching_urls Some of the advantages of the new pattern, compared to the previous one: It no longer uses the [:punct:] named character class. I thought this was universally supported in modern regex engines, but apparently it is not. It does a better job with URLs containing literal parentheses, correctly matching the following URLs that the previous pattern did not: .http://foo.com/more_(than)_one_(parens) http://foo.com/blah_(wikipedia)#cite-1. http://foo.com/blah_(wikipedia)_blah#cite-1. http://foo.com/unicode_(✪)_in_parens, http://foo.com/(something)?after=parens. It now matches mailto: URLs. It correctly guesses that things like “bit.ly/foo” and “is.gd/foo/” are URLs. Basically: something-dot-something-slash-something. teste www.google.com teste https://www.facebook.com. https://app-1.number123.com. http://facebook.com. ftp://facebook.com http://localhost:3000 localhost:3000/ unitedkingdomurl.co.uk this.is.a.url.com/its/still=going?wow shop.facebook.org app.number123.com app1.number123.com app-1.numbEr123.com app.dashes-dash.com www.facebook.com facebook.com fb.com/hello_123 fb.com/hel-lo fb.com/hello/goodbye fb.com/hello/goodbye?okay fb.com/hello/goodbye?okay=alright Hello www.google.com World http://yahoo.com https://www.google.com.tr/admin/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services https://google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services http://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services ftp://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services www.google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services www.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services drive.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services https://www.example.pl http://www.example.com www.example.pl example.com http://blog.example.com http://www.example.com/product http://www.example.com/products?id=1&page=2 http://www.example.com#up http://255.255.255.255 255.255.255.255 shop.facebook.org/derf.html Hello www.google.com World http://yahoo.com https://www.google.com.tr/admin/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services https://google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services http://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services ftp://google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services www.google.com.tr/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services www.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services drive.google.com/test/subPage?qs1=sss1&qs2=sss2&qs3=sss3#Services Will match the following cases http://www.foufos.gr https://www.foufos.gr http://foufos.gr http://www.foufos.gr/kino http://werer.gr www.foufos.gr www.mp3.com www.t.co http://t.co http://www.t.co https://www.t.co www.aa.com http://aa.com http://www.aa.com https://www.aa.com Will NOT match the following www.foufos www.foufos-.gr www.-foufos.gr foufos.gr http://www.foufos http://foufos www.mp3#.com `; // 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