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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\<(\\w+)(?:\\s*\\>|\\s*\\/\\>)?"; final String string = "\n" + "<!DOCTYPE html>\n" + "<html lang=\"el\" dir=\"ltr\" class=\"no-js\">\n" + "<head >\n" + " <meta charset=\"utf-8\" />\n" + " <title>Radial</title>\n" + " <meta name=\"description\" content=\"Η Radial σχεδιάζει και αναπτύσσει websites, οργανώνει online καμπάνιες και δημιουργεί εταιρικές ταυτότητες.\" />\n" + " \n" + " <meta property=\"fb:page_id\" content=\"118981334805256\" />\n" + " <meta property=\"fb:app_id\" content=\"166019300145537\" />\n" + " \n" + " \n" + " <!--[if lt IE 9]><script type=\"text/javascript\" src=\"http://html5shiv.googlecode.com/svn/trunk/html5.js\"></script><![endif]-->\n" + " <script type=\"text/javascript\">(function(H){H.className=H.className.replace(/\\bno-js\\b/,'js')})(document.documentElement);</script>\n" + " \n" + " <link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"http://static.radial.gr/styles/screen.css?43614\" />\n" + " \n" + " <script type=\"text/javascript\" src=\"http://use.typekit.com/ioa2dxy.js\"></script>\n" + " <script type=\"text/javascript\">try{Typekit.load();}catch(e){}</script?\n" + " \n" + " <link rel=\"alternate\" type=\"application/rss+xml\" title=\"Τελευταία έργα\" href=\"/feed/\" />\n" + " \n" + " \n" + " \n" + "</head>\n\n" + "<body id=\"home\" class=\"\">\n\n" + "<header id=\"main-header\"><div class=\"wrapper\">\n" + " <div id=\"logo\"><a href=\"/\"><img src=\"http://static.radial.gr/images/radial-logo.png\" alt=\"Radial\" /></a></div>\n" + " <nav id=\"main-nav\">\n" + " <ul>\n" + " <li><a href=\"/projects/\">Έργα</a></li>\n" + " <li><a href=\"/profile/\">Προφίλ</a></li>\n" + " <li><a href=\"/contact/\">Επικοινωνία</a></li>\n" + " </ul>\n" + " </nav>\n" + " <nav id=\"lang-nav\">\n" + " <span >EΛ</span>\n" + " <a href=\"/en/\">EN</a>\n" + " </nav>\n\n" + "<br />\n\n" + "</div></header>\n\n" + "<script type=\"text/javascript\">\n" + " \n" + " var _gaq = _gaq || [];\n" + " _gaq.push(['_setAccount', 'UA-515952-44']);\n" + " _gaq.push(['_trackPageview']);\n" + " (function() {\n" + " var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;\n" + " ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';\n" + " var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);\n" + " })();\n\n\n" + "</script>\n\n" + "</body>\n" + "</html>\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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