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

/
/
ig

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 = "<a[^>]*?href=([\"\\'])?((?:.(?!\\1|>))*.?)\\1?"; final String string = "<li class=\"navItem \"><a href=\"/services/\" lang=\"de\" hreflang=\"de\">Services</a></li>\n" + "<a class=\"iMacLink\" href=\"/portfolio/\" ><div class=\"iMacOverlay\"></div><div class=\"\">Super</div></a></div>\n" + "<div class=\"addthis_toolbox addthis_default_style\">\n" + "<a itemprop=\"url\" target=\"_blank\" href=\"https://www.facebook.com/any-profile\" title=\"facebook\" class=\"facebookSite\"><span class=\"icon-facebook\"></span></a>\n" + "<a itemprop=\"url\" target=\"_blank\" href=\"https://twitter.com/any-profile\" title=\"twitter\" class=\"twitterSite\"><span class=\"icon-twitter\"></span></a>\n" + "<a itemprop=\"url\" target=\"_blank\" href=\"https://pinterest.com/any-profile\" title=\"pinterest\" class=\"pinterestSite\"><span class=\"icon-pinterest\"></span></a>\n" + "<a itemprop=\"url\" target=\"_blank\" href=\"//feeds.feedburner.comany-profile?format=xml\" title=\"rss\" class=\"rss\"><span class=\"icon-rss\"></span></a>\n" + "</div>\n\n\n" + "<a class=\"social facebookProfil\" href=\"http://www.facebook.com/any-profile\">Facebook</a>\n" + "<a class=\"social facebookProfil\" href='https://www.facebook.com/single-quotes'>Facebook</a>\n" + "<a class=\"social facebookProfil\" href=https://www.facebook.com/no-quotes>Facebook</a>\n" + "<a class=\"social youtubeProfil\" href=\"http://www.youtube.com/user/any-profile\">Youtube</a>\n\n" + "<a class=\"social vimeoProfil\" href=\"http://vimeo.com/any-profile\">Vimeo</a>\n" + "<a class=\"social xingProfil\" href=\"https://www.xing.com/companies/any-profile\">XING</a>\n" + "<a class=\"social twitterProfil\" href=\"https://twitter.com/any-profile\">Folge bei Twitter</a>\n\n" + "<a href=\"https://www.instagram.com/p/CN-Kx40nOW0/\">Instagram Beitrag</a>\n" + "<a href=\"http://instagram.com/quellenhofaachen\">Instagram Profil</a>\n" + "<a href=\"https://www.instagram.com/explore/tags/url\">Instagram Tag-Url</a>\n" + "<A href=\"https://www.Instagram.com/uppercase-link\">Upercase-link</A>\n\n" + "<a href=\"http://instagram.com/unique\">Unique-test http</a>\n" + "<a href=\"//instagram.com/unique\">Unique-test protocol relative</a>\n" + "<a href=\"https://instagram.com/unique\">Unique-test https</a>\n" + "<a href=\"http://www.instagram.com/unique\">Unique-test www</a>\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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