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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(<(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?=((?:\"[\S\s]*?\"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+))\3)?\s*>)[\S\s]*?<\/\2\s*(?=>))|(?:\/?[\w:]+\s*\/?)|(?:[\w:]+\s+(?:\"[\S\s]*?\"|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>)|([^<>]*?)(querry)" test_str = ("<body class=\"mediawiki querry ltr sitedir-ltr ns-0 ns-subject page-International_English_Language_Testing_System skin-vector action-view vector-animateLayout\">\n" " <div id=\"mw-page-base\" class=\"noprint\"></div>\n" " <div id=\"mw-head-base\" class=\"noprint\"></div>\n" " <div id=\"content\" class=\"mw-body\" role=\"main\">\n" " <a id=\"top\"></a>\n\n" "and also a normal querry\n\n" " <div id=\"siteNotice\"><!-- CentralNotice --></div>\n" " <h1 id=\"firstHeading\" class=\"firstHeading\" lang=\"en\"><span dir=\"auto\">International English Language Testing System</span></h1>\n" " <div id=\"bodyContent\" class=\"mw-body-content\">\n" " <div id=\"siteSub\">From Wikipedia, the free encyclopedia</div>\n" " <div id=\"contentSub\">  (Redirected from <a href=\"/w/index.php?title=IELTS&amp;redirect=no\" title=\"IELTS\">IELTS</a>)</div>\n" " <div id=\"jump-to-nav\" class=\"mw-jump\">\n" " Jump to: <a href=\"#mw-navigation\">navigation</a>, <a href=\"#p-search\">search</a>\n" " </div>\n" " <div id=\"mw-content-text\" lang=\"en\" dir=\"ltr\" class=\"mw-content-ltr\"><table class=\"infobox vevent\" cellspacing=\"3\" style=\"border-spacing:3px;width:22em;\">\n" "<caption class=\"summary\">International English Language Testing System</caption>\n" "<tr>\n" "<td colspan=\"2\" style=\"text-align:center;\"><a href=\"/wiki/File:IELTS_logo.svg\" class=\"image\"><img alt=\"IELTS logo.svg\" src=\"//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/300px-IELTS_logo.svg.png\" width=\"300\" height=\"113\" srcset=\"//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/450px-IELTS_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/600px-IELTS_logo.svg.png 2x\" data-file-width=\"778\" data-file-height=\"293\" /></a></td>\n" "</tr>\n" "<tr>\n" "<th scope=\"row\" style=\"text-align:left;\">Acronym</th>\n" "<td>IELTS</td>\n" "</tr>\n" "<tr>\n" "<th scope=\"row\" style=\"text-align:left;\">Type</th>\n" "<td>Standardized test. Available in 2 versions: \"Academic\" and \"General training\".</td>\n" "</tr>\n" "<tr>\n" "<th scope=\"row\" style=\"text-align:left;\">Developer / administrator</th>\n" "<td><a href=\"/wiki/Cambridge_English_Language_Assessment\" title=\"Cambridge English Language Assessment\">Cambridge English Language Assessment</a>, <a href=\"/wiki/British_Council\" title=\"British Council\">British Council</a>, <a href=\"/wiki/IDP_Education\" title=\"IDP Education\">IDP Education</a>.</td>\n" "</tr>\n" "<tr>\n" "<th scope=\"row\" style=\"text-align:left;\">Knowledge/skill(s) tested</th>\n" "<td>Listening, reading, writing and speaking of the <a href=\"/wiki/English_language\" title=\"English language\">English language</a>.</td>\n" "</tr>\n" "<tr>\n" "<th scope=\"row\" style=\"text-align:left;\">Purpose</th>\n" "<td>To assess the English language proficiency of non-native English speakers.</td>\n" "</tr>\n") matches = re.finditer(regex, test_str, re.MULTILINE) 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