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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<!DOCTYPE html>|</?\\s*[a-z-][^>]*\\s*>|(\\&(?:[\\w\\d]+|#\\d+|#x[a-f\\d]+);|<!--[\\s\\S\\n]*?-->)"; final String string = "\n" + "# Above is a blank line, no match.\n\n" + "foo bar baz\n" + "this is a string\n" + "Testing\n" + "<>\n" + "Hello, World\n" + "This is less than <, this is greater than >.\n" + " a < 3 && b > 3\n" + "<<Important Text>>\n" + "# Not HTML-like.\n\n" + "<p>fizz buzz</p>\n" + "<a>this is a string</a>\n" + "this is a <b>string</b>\n" + "<p>Testing</p>\n" + "<img src=\"hello.jpg\">\n" + "<a>Foo</a>\n" + "<input type='submit' value='Ok' />\n" + "<input type='submit' value='Ok'>\n" + "<br/>\n" + "<br>\n" + "<!-- comment -- doesn't work! -->\n" + "<hr>\n" + "Foo &amp; bar\n" + "# These one-line samples are totally HTML-like.\n\n" + "<file-upload>\n" + "<absurd example>\n" + "<closed example></closed>\n" + "# Custom tags.\n\n" + "<a>\n" + "# Not matched by others, but actually valid.\n\n" + "My < weird > string\n" + "# Not actually a false positive; this is valid HTML!\n\n" + "# Sample \"smallest complete HTML document\":\n" + "<!DOCTYPE html>\n" + "<title>testing</title>\n" + "<p>This is a test.</p>\n" + "<strange>This is strange.</strange>\n" + "# And yes, <strange> IS VALID HTML.\n\n" + "résume\n" + "r&eacute;sume\n" + "r&#201;sume\n" + "r&x00C9;sume\n" + "# Entities\n\n" + "# List Tricks\n" + "<ul><li>Foo</li\n" + "><li>Bar</li\n" + "></ul>\n\n" + "# From https://stackoverflow.com/a/51325984/211827\n" + "Hello, World\n" + "This is less than <, this is greater than >.\n" + " a < 3 && b > 3\n" + "<<Important Text>>\n" + "<a> # This actually is HTML, not a false positive.\n" + "<a>Foo</a>\n" + "<input type='submit' value='Ok' /> # XHTML, not HTML...\n" + "<br/> # XHTML again...\n" + "<br> # These didn't work with that answer.\n" + "Foo &amp; bar\n" + "<input type='submit' value='Ok'>\n\n" + "# From https://regex101.com/r/cX0eP2/1\n" + "<a href=bla>sdfsdf</a>\n" + "<div>something</div>\n" + "<br>\n" + "<span>mayhem</div>\n" + "<hr />\n" + "<input name=bla / >\n" + "<div>some<span>thing</span>here</div>\n\n\n" + "# Prepare your eye bleach.\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\">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>"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html