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

/
/
i

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /<a ([^>]*)>([^<]*)(<\/?br\/?>)+([^<]*)<\/a/i; // Alternative syntax using RegExp constructor // const regex = new RegExp('<a ([^>]*)>([^<]*)(<\\\/?br\\\/?>)+([^<]*)<\\\/a', 'i') const str = `<h1>Finantza-trebakuntza</h1> <p> Izaera praktikoa duten ikastaro-eskaintza osatua egiten du, enpresaren kudeaketa ekonomiko-finantzarioaren eremu desberdinen inguruan eta bere beharretara egokitua. </p> <ul class='cuadrados2 tres clearfix'><li class='lineas3'>Finantza- trebakuntzan aitzindariak</li> <li class='lineas3'>18.500<br></br> parte hartzaile baino gehiago</li> <li class='lineas3'>Ikastaro<br></br> praktiko eta <br></br> eraginkorrak</li> </ul><ul class='cuadrados dos clearfix'><li class='lineas2'><a href='http://elkargi2015.pre.wegetit.ws/eu/elkargi-consultores-trebakuntza/Finantza-Ikasgelako-ikastaroak/316.aspx'>Finantza Ikasgelako<br></br> ikastaroak</a></li> <li class='lineas1'><a href='http://elkargi2015.pre.wegetit.ws/eu/elkargi-consultores-trebakuntza/Ikastaro-presentzialak/338.aspx'>Ikastaro ez presentzialak</a></li> </ul><ul class='cuadrados dos clearfix'><li class='lineas1'><a href='http://elkargi2015.pre.wegetit.ws/eu/elkargi-consultores-trebakuntza/Company-trebakuntza-ikastaroak/337.aspx'>Trebakuntza in-company</a></li> <li class='lineas2'><a href='http://elkargi2015.pre.wegetit.ws/eu/elkargi-consultores-trebakuntza/Finantza-Zuzendaritzako-Programa-Exekutiboa/336.aspx'>Finantza Zuzendaritzako Programa Exekutiboa</a></li> </ul><br></br> <a href='http://elkargi2015.pre.wegetit.ws/eu/elkargi-consultores-trebakuntza/finantza-zuzendaritzako-programa-exekutiboa/pedf-jardunaldi-informatiboak/540.aspx' title='PEDF'><img src='http://www.elkargi.es/uploads/images/Banners/2011/PEDF_oct_eusk_especial.jpg' alt='PEDF'></img></a><br></br></div> `; const subst = `<a $1>$2 $4</a`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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