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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<xxxx\\b[^<]*(?:(?!<\\/yyyy>)<[^<]*)*<\\/yyyy>"; final String string = "<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\" />"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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