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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(var preferences = {)[\s\S]*(};)", flags=re.MULTILINE) test_str = ("<!DOCTYPE html>\n" "<html>\n" " <head>\n" " <meta http-equiv='x-ua-compatible' content='IE=edge,chrome=1' />\n" " <meta name=\"robots\" content=\"nofollow\" />\n" " <meta name=\"robots\" content=\"noindex\" />\n" " <meta name=\"robots\" content=\"noarchive\" />\n" " <meta http-equiv=\"Cache-Control\" content=\"private, no-cache, no-store, must-revalidate, max-age=0\" />\n" " <meta http-equiv=\"Pragma\" content=\"no-cache\" />\n" " <meta http-equiv=\"Expires\" content=\"0\" />\n" " <meta http-equiv=\"Expires\" content=\"Tue, 01 Jan 1980 1:00:00 GMT\" />\n" " <meta charset='UTF-8' />\n" " <title>BLANK - FILL WITH CLIENT TITLE</title>\n" " <link href='css/bpdev.css' rel='stylesheet' type='text/css' />\n" " <script src='https://code.jquery.com/jquery-1.11.1.min.js'></script>\n" " <script>!window.jQuery && document.write('<script src=\"common/js/jquery/jquery-1.11.1.min.js\"><\\/script>');</script>\n" " <link rel='shortcut icon' href='images/favicon.ico' type='image/x-icon' />\n" " <style id=\"antiClickjack\">body{display:none !important;}</style>\n" " </head>\n" " <body id='userTools'>\n" " <div id='notificationContainer' data-automation='notification_window'></div>\n" " <div id='overlay' class='modalOverlay' data-automation='modal_overlay'></div>\n" " <div id='dialog' class='modal' data-automation='modal_window'></div>\n" " <div id='container'>\n" " <div id='header' data-automation='header'></div>\n" " <div id='loader' data-automation='content_loader'></div>\n" " <div id='content' data-automation='content_area'></div>\n" " </div>\n" " <div id='copyFooter' class='copyright' data-automation='copyright_footer'></div>\n" " <script src='common/js/gateway.framework-min.js' type='text/javascript'></script>\n" " <script src='common/js/gateway.app-min.js' type='text/javascript'></script>\n" " <script type='text/javascript'>\n" " if (self === top) {\n" " var antiClickjack = document.getElementById('antiClickjack');\n" " antiClickjack.parentNode.removeChild(antiClickjack);\n" " } else {\n" " top.location = self.location;\n" " }\n" " (function($) {\n" " var preferences = {\n" " logo : 'images/logo.png',\n" " logoWidth : 250,\n" " logoHeight : 38,\n" " logoAlt : '',\n" " logoLink : '',\n" " logoutURL : '../../pkmslogout'\n" " };\n" " Gateway.startGateway(preferences, true);\n" " }(jQuery));\n" " </script>\n" " </body>\n" "</html>") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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