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"
"
g

Test String

Code Generator

Language

Generated Code

re = /<!DOCTYPE html>|<\/?\s*[a-z-][^>]*\s*>|(\&(?:[\w\d]+|#\d+|#x[a-f\d]+);|<!--[\s\S\n]*?-->)/ str = ' # Above is a blank line, no match. foo bar baz this is a string Testing <> Hello, World This is less than <, this is greater than >. a < 3 && b > 3 <<Important Text>> # Not HTML-like. <p>fizz buzz</p> <a>this is a string</a> this is a <b>string</b> <p>Testing</p> <img src="hello.jpg"> <a>Foo</a> <input type=\'submit\' value=\'Ok\' /> <input type=\'submit\' value=\'Ok\'> <br/> <br> <!-- comment -- doesn\'t work! --> <hr> Foo &amp; bar # These one-line samples are totally HTML-like. <file-upload> <absurd example> <closed example></closed> # Custom tags. <a> # Not matched by others, but actually valid. My < weird > string # Not actually a false positive; this is valid HTML! # Sample "smallest complete HTML document": <!DOCTYPE html> <title>testing</title> <p>This is a test.</p> <strange>This is strange.</strange> # And yes, <strange> IS VALID HTML. résume r&eacute;sume r&#201;sume r&x00C9;sume # Entities # List Tricks <ul><li>Foo</li ><li>Bar</li ></ul> # From https://stackoverflow.com/a/51325984/211827 Hello, World This is less than <, this is greater than >. a < 3 && b > 3 <<Important Text>> <a> # This actually is HTML, not a false positive. <a>Foo</a> <input type=\'submit\' value=\'Ok\' /> # XHTML, not HTML... <br/> # XHTML again... <br> # These didn\'t work with that answer. Foo &amp; bar <input type=\'submit\' value=\'Ok\'> # From https://regex101.com/r/cX0eP2/1 <a href=bla>sdfsdf</a> <div>something</div> <br> <span>mayhem</div> <hr /> <input name=bla / > <div>some<span>thing</span>here</div> # Prepare your eye bleach. <p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Notre sp&eacute;cialit&eacute; : offrir de l&rsquo;assistance &agrave; plus d&rsquo;un million de Qu&eacute;b&eacute;cois. Nous sommes fiers d&rsquo;aider! Participez vous aussi &agrave; cette mission en r&eacute;alisant les r&ecirc;ves d&rsquo;aventure, de d&eacute;tente et de d&eacute;couverte de nos membres et clients au sein de notre agence de voyages.</span></span></p>\\r\\n\\r\\n<p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Joignez-vous &agrave; nous! Vous b&eacute;n&eacute;ficierez de nombreux avantages :&nbsp;</span></span></p>\\r\\n\\r\\n<ul style="line-height:normal">\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Salaire fixe, et primes lorsque vous d&eacute;passez vos objectifs.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">20 jours de cong&eacute; apr&egrave;s une ann&eacute;e.</span></span></li>\\r\\n\\t<li><span style="font-size:12px"><span style="font-family:Arial">R&eacute;gime de retraite - CAA-Qu&eacute;bec &eacute;gale votre mise!</span></span></li>\\r\\n\\t<li><span style="font-size:12px"><span style="font-family:Arial">Assurance collective compl&egrave;te (soins m&eacute;dicaux et param&eacute;dicaux, invalidit&eacute;, etc.).</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Rabais trippants chez nos partenaires, dans nos centres Voyages et pour vos assurances.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Plus de 1,2 million de membres comme clients potentiels.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Soutien administratif pour vous concentrer sur la vente de voyages.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Allocation g&eacute;n&eacute;reuse pour les &eacute;ducotours.</span></span></li>\\r\\n</ul>\\r\\n\\r\\n<p style="line-height:normal; margin-bottom:0px; margin-top:0px">&nbsp;</p>\\r\\n\\r\\n<p style="line-height:normal; margin-bottom:0px; margin-top:0px"><img class="largeimage" src="https://gestiondestalents.caaquebec.com/caa/login/caa/_attachments/news_files/activex/image%20conseiller%20en%20voyage.JPG" style="line-height:normal; width:100%" /></p>\\r\\n\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t <br/><br/>\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t<p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">En tant que conseiller en voyages, vos principales t&acirc;ches et responsabilit&eacute;s seront celles-ci :</span></span></p>\\r\\n\\r\\n<ul style="line-height:normal">\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">R&eacute;aliser une analyse des besoins des clients et leur fournir des renseignements pr&eacute;cis et utiles.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Effectuer les r&eacute;servations et achats (forfaits, croisi&egrave;res, circuits, h&ocirc;tels, automobiles et assurances voyage).</span></span></li>\\r\\n</ul>\\r\\n\\r\\n<p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Vous occuperez un poste r&eacute;gulier &agrave; temps plein (35&nbsp;heures par semaine). L&rsquo;horaire sera variable et vous devrez parfois travailler le soir et la fin de semaine afin de bien servir les voyageurs.</span></span></p>\\r\\n\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t\\r\\n\\t\\t <br/><br/>\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t<p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Nous sommes toujours &agrave; la recherche de personnes de talent. Mais vous devrez avoir un profil pr&eacute;cis pour ce poste!</span></span></p>\\r\\n\\r\\n<ul style="line-height:normal">\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Dipl&ocirc;me d&rsquo;&eacute;tudes coll&eacute;giales en tourisme ou formation d&rsquo;agent de voyages.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">2 &agrave; 3 ann&eacute;es d&rsquo;exp&eacute;rience comme conseiller en voyages.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Certificat de conseiller en voyages de l&rsquo;Office de la protection du consommateur, ou &ecirc;tre en mesure de l&rsquo;obtenir.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Connaissance des syst&egrave;mes de d&eacute;livrance de billets : GDS, Galileo/Apollo, PcVoyages et SIREV (un atout).</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Ma&icirc;trise du fran&ccedil;ais et de l&rsquo;anglais.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Professionnalisme, attention aux besoins des clients et volont&eacute; d&rsquo;offrir un service de qualit&eacute;.</span></span></li>\\r\\n\\t<li style="line-height: normal;"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal">Souci d&rsquo;atteindre les objectifs de vente.</span></span></li>\\r\\n</ul>\\r\\n\\r\\n<p style="line-height:normal; margin-top:0px"><span style="font-size:12px; line-height:normal"><span style="font-family:Arial; line-height:normal"><span style="line-height:normal">Si explorer de nouveaux horizons vous passionne, et que vous aimez aider d&rsquo;autres personnes &agrave; d&eacute;couvrir le monde, vous serez heureux &agrave; Voyages CAA-Qu&eacute;bec. Postulez d&egrave;s aujourd&rsquo;hui. Nous vous attendons avec impatience!</span></span></span></p>' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html