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 = /^http[s]?:\/\/[^\/]*\.[a-z]+\/?$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^http[s]?:\\\/\\\/[^\\\/]*\\.[a-z]+\\\/?$', 'gm') const str = `https://www.feetrader.com/jobPostings http://www.bienesonline.es/asociarse/ http://www.bienesonline.mx/asociarse/ http://www.bienesonline.cl/asociarse/ http://www.bienesonline.co/asociarse/ http://www.geralimoveis.com.br/produtos/ http://usa.bienesonline.com/asociarse/ http://www.informatik.uni-linz.ac.at/jobs/ http://informatik.jku.at/jobs/ https://2012.nosql-matters.org/bcn/ https://www.mapmeo.com/partner http://www.revistapremier.com.br/contemporanea/ https://zippyapp.com/business http://graph.storn.es/ http://www.volcanicinternet.com/portfolio/ http://imobsync.com.br/ http://trovit.com.isdownorblocked.com/ http://infoday.hoyu.edu.hk/test/ http://2016.desymfony.com/patrocinadores https://osclass.com/en/ https://imobtic.com.br/ http://www.trovit.at-s.seohighscore.com/ https://dom.yuga.ru/sites/ https://www.kadaza.com/classifieds http://www.oxleyrobert.com/ http://blog.trovit.de/ http://job.trovit.at/ https://www.sistemarsi.com/privacy https://www.docjobs.at/ https://www.bienesonline.com.ar/asociarse/`; // 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