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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)<xxxx\b[^<]*(?:(?!<\/yyyy>)<[^<]*)*<\/yyyy>`) var 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' /> <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' /> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/jquery/jquery.js?ver=1.12.4'></script> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.4.1'></script> <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> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/plugins/add-to-any/addtoany.min.js?ver=1.0'></script> <script type='text/javascript'> 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"}}; </script> <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> <xxxx type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/mediaelement/mediaelement-migrate.min.js?ver=4.9.8'></yyyy> <script type='text/javascript'> /* <![CDATA[ */ var _wpmejsSettings = {"pluginPath":"\/blog\/wp-includes\/js\/mediaelement\/","classPrefix":"mejs-","stretching":"responsive"}; /* ]]> */ </script> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-includes/js/mediaelement/wp-mediaelement.min.js?ver=4.9.8'></script> <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> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/jquery.flexslider.min.js?ver=2.1'></script> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/jquery.touchSwipe.min.js?ver=1.6.6'></script> <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> <!--[if lt IE 9]> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/html5.min.js?ver=3.7.3'></script> <![endif]--> <!--[if (gte IE 6)&(lte IE 8)]> <script type='text/javascript' src='https://www.markmallett.com/blog/wp-content/themes/vantage/js/selectivizr.min.js?ver=1.0.2'></script> <![endif]--> <script type='text/javascript'> /* <![CDATA[ */ 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>"}; /* ]]> */ </script> <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> <link rel='https://api.w.org/' href='https://www.markmallett.com/blog/wp-json/' /> <link rel="EditURI" type="application/rsd+xml" title="RSD" href="https://www.markmallett.com/blog/xmlrpc.php?rsd" /> <link rel="wlwmanifest" type="application/wlwmanifest+xml" href="https://www.markmallett.com/blog/wp-includes/wlwmanifest.xml" /> <link rel='prev' title='God Has a Face' href='https://www.markmallett.com/blog/2017/12/25/god-has-a-face/' /> <link rel='next' title='You Be Noah' href='https://www.markmallett.com/blog/2018/01/04/you-be-noah/' /> <meta name="generator" content="WordPress 4.9.8" /> <link rel='shortlink' href='https://wp.me/p8tvP8-8tm' /> <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" /> <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" />` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", 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 Golang, please visit: https://golang.org/pkg/regexp/