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

/
/
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 = "(((1[0-9]{2})|(2[0-5]{2})|[0-9]{1,2})\\.){3}(((1[0-9]{2})|(2[0-5]{2})|[0-9]{1,2})):(\\d{5})"; final String string = "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n" + "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" lang=\"en\">\n" + " <head>\n" + " <meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\" />\n" + " <meta name=\"title\" content=\"eBot :: Your ingame bot manager for CS:GO\" />\n" + " <title>eBot :: Your ingame bot manager for CS:GO</title>\n" + " <link rel=\"shortcut icon\" type=\"image/png\" href=\"/favicon.png\" />\n" + " <link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/bootstrap.min.css\" />\n" + "<link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/bootstrap-responsive.min.css\" />\n" + "<link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/tipsy.css\" />\n" + "<link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/datatable.bootstrap.css\" />\n" + "<link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/flags.css\" />\n" + "<link rel=\"stylesheet\" type=\"text/css\" media=\"screen\" href=\"/css/hubinfo.min.css\" />\n" + " <script type=\"text/javascript\" src=\"/js/jquery-1.8.2.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/bootstrap.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/jquery.validate.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/jquery.tipsy.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/jquery.tablesorter.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/jquery.datatable.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/datatable.bootstrap.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/heatmap.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/raphael-min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/jquery.iphone-switch.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/hubinfo.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/pnotify.custom.min.js\"></script>\n" + "<script type=\"text/javascript\" src=\"/js/aes.js\"></script>\n" + " <style type=\"text/css\">\n" + " body {\n" + " padding-top: 60px;\n" + " padding-bottom: 40px;\n" + " }\n" + " .sidebar-nav {\n" + " padding: 9px 0;\n" + " }\n" + " </style>\n" + " <!-- Le HTML5 shim, for IE6-8 support of HTML5 elements -->\n" + " <!--[if lt IE 9]>\n" + " <script src=\"http://html5shim.googlecode.com/svn/trunk/html5.js\"></script>\n" + " <![endif]-->\n" + " </head>\n" + " <body>\n" + " <script>\n" + " function submitForm(id) {\n" + " $(\"#\" + id).submit();\n" + " }\n\n" + " var socketIoAddress = \"176.31.211.228:12370\";\n" + " var socket = null;\n" + " var socketIoLoaded = false;\n" + " var loadingSocketIo = false;\n" + " var callbacks = new Array();\n" + " function initSocketIo(callback) {\n" + " callbacks.push(callback);\n" + " if (loadingSocketIo) {\n" + " return;\n" + " }\n" + " \n" + " if (socketIoLoaded) {\n" + " if (typeof callback == \"function\") {\n" + " callback(socket);\n" + " }\n" + " return;\n" + " }\n" + " \n" + " loadingSocketIo = true;\n" + " $.getScript(\"http://\"+socketIoAddress+\"/socket.io/socket.io.js\", function(){\n" + " socket = io.connect(\"http://\"+socketIoAddress);\n" + " socket.on('connect', function(){ \n" + " socketIoLoaded = true;\n" + " loadingSocketIo = false;\n" + " if (typeof callback == \"function\") {\n" + " callback(socket);\n" + " }\n" + " for (var c in callbacks) {\n" + " callbacks[c](socket);\n" + " }\n" + " //callbacks = new Array();\n" + " });\n" + " });\n" + " }\n" + " </script>\n" + " <div class=\"navbar navbar-inverse navbar-fixed-top\">\n" + " <div class=\"navbar-inner\">\n" + " <div class=\"container-fluid\">\n" + " <a class=\"btn btn-navbar\" data-toggle=\"collapse\" data-target=\".nav-collapse\">\n" + " <span class=\"icon-bar\"></span>\n" + " <span class=\"icon-bar\"></span>\n" + " <span class=\"icon-bar\"></span>\n" + " </a>\n" + " <a class=\"brand\" href=\"/\">eBot-CSGO</a>\n" + " <div class=\"nav-collapse collapse\">\n" + " <div style=\"line-height: 35px; float: right; margin-right: 10px;\">\n" + " <form style=\"display:inline; margin-left: 5px; cursor: pointer\" action=\"/switch/lang/fr\" method=\"POST\" id=\"langFr\"><input type=\"hidden\" name=\"referer\" value=\"/servers\" /><img onclick=\"javascript:submitForm('langFr')\" src=\"/images/fr.png\" /></form>\n" + " <form style=\"display:inline; margin-left: 5px; cursor: pointer\" action=\"/switch/lang/en\" method=\"POST\" id=\"langEn\"><input type=\"hidden\" name=\"referer\" value=\"/servers\" /><img onclick=\"javascript:submitForm('langEn')\" src=\"/images/en.png\" /></form>\n" + " <form style=\"display:inline; margin-left: 5px; cursor: pointer\" action=\"/switch/lang/de\" method=\"POST\" id=\"langDe\"><input type=\"hidden\" name=\"referer\" value=\"/servers\" /><img onclick=\"javascript:submitForm('langDe')\" src=\"/images/de.png\" /></form>\n" + " <form style=\"display:inline; margin-left: 5px; cursor: pointer\" action=\"/switch/lang/cn\" method=\"POST\" id=\"langCn\"><input type=\"hidden\" name=\"referer\" value=\"/servers\" /><img onclick=\"javascript:submitForm('langCn')\" src=\"/images/cn.gif\" /></form>\n" + " </div>\n" + " \n" + " <p class=\"navbar-text pull-right\">\n" + " Logged in as <a href=\"#\" class=\"navbar-link\">tictax</a>\n" + " </p>\n" + " <ul class=\"nav\">\n" + " <li class=\"active\"><a href=\"/\">Home</a></li>\n" + " <li><a href=\"http://www.esport-tools.net/ebot\">Help</a></li>\n" + " <li><a href=\"http://www.esport-tools.net/about\">About</a></li>\n" + " </ul>\n" + " </div>\n" + " </div>\n" + " </div>\n" + " </div>\n\n" + " <div class=\"container-fluid\">\n" + " <div class=\"row-fluid\">\n" + " <div class=\"span2\">\n" + " <div class=\"well sidebar-nav\">\n" + " <script>\n" + " function goToMatch() {\n" + " var id = $(\"#match_id_go\").val();\n" + " if (id > 0)\n" + " document.location.href = \"/matchs/view/\"+id;\n" + " };\n" + " </script>\n" + " <ul class=\"nav nav-list\">\n" + " <li class=\"nav-header\">Main Menu</li>\n" + " <li ><a href=\"/\">Home</a></li>\n" + " <li ><a href=\"/stats\">Statistics</a></li>\n" + " <li ><a href=\"/credits\">Credits</a></li>\n" + " <!--<li ><a href=\"/main/ingame\">Ingame Help</a></li>-->\n" + " <li class=\"nav-header\">Match Menu</li>\n" + " <li ><a href=\"/matchs/current/1\">Matches in Progress <span class=\"badge badge-info\">39</span></a></li>\n" + " <li ><a href=\"/matchs/archived/1\">Archived Matches</a></li>\n" + " <li ><a href=\"/seasons\">Seasons Overview</a></li>\n" + " <li class=\"nav-header\">Match Management</li>\n" + " <li ><a href=\"/matchs/create\">Create a match</a></li>\n" + " <li ><a href=\"/matchs/user\">My matchs <span class=\"badge badge-info\">0</span></a></li>\n" + " <li class=\"nav-header\">Team Management</li>\n" + " <li><a href=\"/teams/create\">Create Team</a></li>\n" + " <li><a href=\"/teams\">Team Management</a></li>\n" + " <li class=\"nav-header\">Server Management</li>\n" + " <li ><a href=\"/servers/create\">Add Gameserver</a></li>\n" + " <li><a href=\"/servers\">Server Management</a></li>\n" + " <li class=\"nav-header\">Statistics</li>\n" + " <li ><a href=\"/stats/global\">Global Statistics</a></li>\n" + " <li ><a href=\"/stats/maps\">Statistics by Map</a></li>\n" + " <li ><a href=\"/stats/weapons\">Statistics by Weapon</a></li>\n" + " </ul>\n" + " </div>\n" + "</div>\n" + " <div class=\"span10\">\n" + " \n" + " \n" + " <h3>Server Management (1/2)</h3>\n" + "<hr/>\n" + "<table class=\"table table-striped\">\n" + " <thead>\n" + " <tr>\n" + " <th>#ID</th>\n" + " <th>IP Adress</th>\n" + " <th>Name</th>\n" + " <th>used?</th>\n" + " <th>Action</th>\n" + " </tr>\n" + " </thead>\n" + " <tbody>\n" + " <tr>\n" + " <td width=\"30\">3243</td>\n" + " <td width=\"200\">85.14.230.26:27015</td>\n" + " <td>Xylonm Gameserver</td>\n" + " <td width=\"100\">\n" + " <img src=\"/images/icons/flag_red.png\" /> not used </td>\n" + " <td width=\"100\">\n" + " <a href=\"/servers/delete/3243\"><button class=\"btn btn-danger\">Delete</button></a>\n" + " </td>\n" + " </tr>\n" + " </tbody>\n\n" + "</table> </div>\n" + " </div>\n\n" + " <!-- Please, don't remove the brand -->\n" + " <footer class=\"footer\">\n" + " <p>&copy; <a target=\"_blank\" href=\"http://www.esport-tools.net/ebot\">eSport-tools</a> 2012-2013 - 3.1.0 Public - By deStrO &amp; Basert - Follow me on <a target=\"_blank\" href=\"https://twitter.com/deStrO_BE\">Twitter</a> - Propulsed by <a target=\"_blank\" href=\"http://twitter.github.com/bootstrap\">Bootstrap</a> & <a target=\"_blank\" href=\"http://www.symfony-project.com\">Symfony</a> - Follow eBot on <a target=\"_blank\" href=\"https://github.com/deStrO/eBot-CSGO\">GitHub</a></p>\n" + " </footer>\n\n" + "<form action=\"https://www.paypal.com/cgi-bin/webscr\" method=\"post\" target=\"_top\">\n" + "<input type=\"hidden\" name=\"cmd\" value=\"_donations\">\n" + "<input type=\"hidden\" name=\"business\" value=\"destro@esport-tools.net\">\n" + "<input type=\"hidden\" name=\"lc\" value=\"BE\">\n" + "<input type=\"hidden\" name=\"item_name\" value=\"eSport-tools.net\">\n" + "<input type=\"hidden\" name=\"no_note\" value=\"0\">\n" + "<input type=\"hidden\" name=\"currency_code\" value=\"EUR\">\n" + "<input type=\"hidden\" name=\"bn\" value=\"PP-DonationsBF:btn_donateCC_LG.gif:NonHostedGuest\">\n" + "<input type=\"image\" src=\"https://www.paypalobjects.com/en_US/BE/i/btn/btn_donateCC_LG.gif\" border=\"0\" name=\"submit\" alt=\"PayPal - The safer, easier way to pay online!\">\n" + "<img alt=\"\" border=\"0\" src=\"https://www.paypalobjects.com/fr_XC/i/scr/pixel.gif\" width=\"1\" height=\"1\">\n" + "</form>\n" + " </div>\n" + " <script type=\"text/javascript\">\n\n" + " var _gaq = _gaq || [];\n" + " _gaq.push(['_setAccount', 'UA-22008669-4']);\n" + " _gaq.push(['_trackPageview']);\n\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" + "</script>\n" + " </body>\n" + "</html>\n"; 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