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"<xxxx\b[^<]*(?:(?!<\/yyyy>)<[^<]*)*<\/yyyy>" test_str = ("<link rel='stylesheet' id='social-logos-css' href='https://www.markmallett.com/blog/wp-content/plugins/jetpack/_inc/social-logos/social-logos.min.css?ver=1' type='text/css' media='all' />\n" "<link rel='stylesheet' id='jetpack_css-css' href='https://www.markmallett.com/blog/wp-content/plugins/jetpack/css/jetpack.css?ver=6.5' type='text/css' media='all' />\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/jquery/jquery.js?ver=1.12.4'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.4.1'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/plugins/footnotes/class/../js/jquery.tools.min.js?ver=4.9.8'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/plugins/add-to-any/addtoany.min.js?ver=1.0'></script>\n" "<script type='text/javascript'>\n" "var mejsL10n = {\"language\":\"en\",\"strings\":{\"mejs.install-flash\":\"You are using a browser that does not have Flash player enabled or installed. Please turn on your Flash player plugin or download the latest version from https:\\/\\/get.adobe.com\\/flashplayer\\/\",\"mejs.fullscreen-off\":\"Turn off Fullscreen\",\"mejs.fullscreen-on\":\"Go Fullscreen\",\"mejs.download-video\":\"Download Video\",\"mejs.fullscreen\":\"Fullscreen\",\"mejs.time-jump-forward\":[\"Jump forward 1 second\",\"Jump forward %1 seconds\"],\"mejs.loop\":\"Toggle Loop\",\"mejs.play\":\"Play\",\"mejs.pause\":\"Pause\",\"mejs.close\":\"Close\",\"mejs.time-slider\":\"Time Slider\",\"mejs.time-help-text\":\"Use Left\\/Right Arrow keys to advance one second, Up\\/Down arrows to advance ten seconds.\",\"mejs.time-skip-back\":[\"Skip back 1 second\",\"Skip back %1 seconds\"],\"mejs.captions-subtitles\":\"Captions\\/Subtitles\",\"mejs.captions-chapters\":\"Chapters\",\"mejs.none\":\"None\",\"mejs.mute-toggle\":\"Mute Toggle\",\"mejs.volume-help-text\":\"Use Up\\/Down Arrow keys to increase or decrease volume.\",\"mejs.unmute\":\"Unmute\",\"mejs.mute\":\"Mute\",\"mejs.volume-slider\":\"Volume Slider\",\"mejs.video-player\":\"Video Player\",\"mejs.audio-player\":\"Audio Player\",\"mejs.ad-skip\":\"Skip ad\",\"mejs.ad-skip-info\":[\"Skip in 1 second\",\"Skip in %1 seconds\"],\"mejs.source-chooser\":\"Source Chooser\",\"mejs.stop\":\"Stop\",\"mejs.speed-rate\":\"Speed Rate\",\"mejs.live-broadcast\":\"Live Broadcast\",\"mejs.afrikaans\":\"Afrikaans\",\"mejs.albanian\":\"Albanian\",\"mejs.arabic\":\"Arabic\",\"mejs.belarusian\":\"Belarusian\",\"mejs.bulgarian\":\"Bulgarian\",\"mejs.catalan\":\"Catalan\",\"mejs.chinese\":\"Chinese\",\"mejs.chinese-simplified\":\"Chinese (Simplified)\",\"mejs.chinese-traditional\":\"Chinese (Traditional)\",\"mejs.croatian\":\"Croatian\",\"mejs.czech\":\"Czech\",\"mejs.danish\":\"Danish\",\"mejs.dutch\":\"Dutch\",\"mejs.english\":\"English\",\"mejs.estonian\":\"Estonian\",\"mejs.filipino\":\"Filipino\",\"mejs.finnish\":\"Finnish\",\"mejs.french\":\"French\",\"mejs.galician\":\"Galician\",\"mejs.german\":\"German\",\"mejs.greek\":\"Greek\",\"mejs.haitian-creole\":\"Haitian Creole\",\"mejs.hebrew\":\"Hebrew\",\"mejs.hindi\":\"Hindi\",\"mejs.hungarian\":\"Hungarian\",\"mejs.icelandic\":\"Icelandic\",\"mejs.indonesian\":\"Indonesian\",\"mejs.irish\":\"Irish\",\"mejs.italian\":\"Italian\",\"mejs.japanese\":\"Japanese\",\"mejs.korean\":\"Korean\",\"mejs.latvian\":\"Latvian\",\"mejs.lithuanian\":\"Lithuanian\",\"mejs.macedonian\":\"Macedonian\",\"mejs.malay\":\"Malay\",\"mejs.maltese\":\"Maltese\",\"mejs.norwegian\":\"Norwegian\",\"mejs.persian\":\"Persian\",\"mejs.polish\":\"Polish\",\"mejs.portuguese\":\"Portuguese\",\"mejs.romanian\":\"Romanian\",\"mejs.russian\":\"Russian\",\"mejs.serbian\":\"Serbian\",\"mejs.slovak\":\"Slovak\",\"mejs.slovenian\":\"Slovenian\",\"mejs.spanish\":\"Spanish\",\"mejs.swahili\":\"Swahili\",\"mejs.swedish\":\"Swedish\",\"mejs.tagalog\":\"Tagalog\",\"mejs.thai\":\"Thai\",\"mejs.turkish\":\"Turkish\",\"mejs.ukrainian\":\"Ukrainian\",\"mejs.vietnamese\":\"Vietnamese\",\"mejs.welsh\":\"Welsh\",\"mejs.yiddish\":\"Yiddish\"}};\n" "</script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/mediaelement/mediaelement-and-player.min.js?ver=4.2.6-78496d1'></script>\n" "<xxxx type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/mediaelement/mediaelement-migrate.min.js?ver=4.9.8'></yyyy>\n" "<script type='text/javascript'>\n" "/* <![CDATA[ */\n" "var _wpmejsSettings = {\"pluginPath\":\"\\/blog\\/wp-includes\\/js\\/mediaelement\\/\",\"classPrefix\":\"mejs-\",\"stretching\":\"responsive\"};\n" "/* ]]> */\n" "</script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/mediaelement/wp-mediaelement.min.js?ver=4.9.8'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/plugins/audio-player-by-clammr/js/clammr-audio-player.js?ver=4.9.8'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/jquery.flexslider.min.js?ver=2.1'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/jquery.touchSwipe.min.js?ver=1.6.6'></script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/jquery.theme-main.min.js?ver=1.7.11'></script>\n" "<!--[if lt IE 9]>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/html5.min.js?ver=3.7.3'></script>\n" "<![endif]-->\n" "<!--[if (gte IE 6)&(lte IE 8)]>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/selectivizr.min.js?ver=1.0.2'></script>\n" "<![endif]-->\n" "<script type='text/javascript'>\n" "/* <![CDATA[ */\n" "var mobileNav = {\"search\":{\"url\":\"https:\\/\\/www.markmallett.com\\/blog\",\"placeholder\":\"Search\"},\"text\":{\"navigate\":\"Menu\",\"back\":\"Back\",\"close\":\"Close\"},\"nextIconUrl\":\"https:\\/\\/www.markmallett.com\\/blog\\/wp-content\\/themes\\/vantage\\/inc\\/mobilenav\\/images\\/next.png\",\"mobileMenuClose\":\"<i class=\\\"fa fa-times\\\"><\\/i>\"};\n" "/* ]]> */\n" "</script>\n" "<script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/inc/mobilenav/js/mobilenav.min.js?ver=1.7.11'></script>\n" "<link rel='https://api.w.org/' href='https://www.markmallett.com/blog/wp-json/' />\n" "<link rel=\"EditURI\" type=\"application/rsd+xml\" title=\"RSD\" href=\"https://www.markmallett.com/blog/xmlrpc.php?rsd\" />\n" "<link rel=\"wlwmanifest\" type=\"application/wlwmanifest+xml\" href=\"https://www.markmallett.com/blog/wp-includes/wlwmanifest.xml\" /> \n" "<link rel='prev' title='God Has a Face' href='https://www.markmallett.com/blog/2017/12/25/god-has-a-face/' />\n" "<link rel='next' title='You Be Noah' href='https://www.markmallett.com/blog/2018/01/04/you-be-noah/' />\n" "<meta name=\"generator\" content=\"WordPress 4.9.8\" />\n" "<link rel='shortlink' href='https://wp.me/p8tvP8-8tm' />\n" "<link rel=\"alternate\" type=\"application/json+oembed\" href=\"https://www.markmallett.com/blog/wp-json/oembed/1.0/embed?url=https%3A%2F%2Fwww.markmallett.com%2Fblog%2F2018%2F01%2F02%2Fthe-relics-and-the-message%2F\" />\n" "<link rel=\"alternate\" type=\"text/xml+oembed\" href=\"https://www.markmallett.com/blog/wp-json/oembed/1.0/embed?url=https%3A%2F%2Fwww.markmallett.com%2Fblog%2F2018%2F01%2F02%2Fthe-relics-and-the-message%2F&#038;format=xml\" />") 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