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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(((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})" test_str = ("<!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") matches = re.finditer(regex, test_str) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html