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

/
/
img

Test String

Code Generator

Language

Generated Code

const regex = /<!-- AppInternalsXpert BMX Integration Begin -->(.*[\s\S]*)<!-- AppInternalsXpert BMX Integration End -->/img; // Alternative syntax using RegExp constructor // const regex = new RegExp('<!-- AppInternalsXpert BMX Integration Begin -->(.*[\\s\\S]*)<!-- AppInternalsXpert BMX Integration End -->', 'img') const str = ` <script> \$(function() { \$( ".tabs" ).tabs(); }); </script> <!-- AppInternalsXpert BMX Integration Begin --> <script> if(!RVBD_EUE){ var RVBD_EUE={startJS:Number(new Date()), clientId:'',appId:1, collector:'apmperformance.correios.com.br', collectorHttpPort:80, collectorHttpsPort:443, sv:'0401', ajax:true, sync:true, ajaxResponseTime:true}; (function(){ var w=window,l=w.addEventListener,m=w.attachEvent, d=document,s='script',t='load',o=RVBD_EUE, r=(('https:'===d.location.protocol)? 'https://apmperformance.correios.com.br:443': 'http://apmperformance.correios.com.br:80')+ '/jsi/riverbed_appinternals.d.'+ (o.ajax?'ajax.js':'js'),p=('onpagehide' in w),e=p?'pageshow':t, j=d.createElement(s),x=d.getElementsByTagName(s)[0], h=function(y){o.ldJS=o.ldJS||new Date();o.per=y?y.persisted:null;}, i=function(){o.ld=1;};o.cookie=d.cookie;d.cookie= '_op_aixPageId=0; path=/; expires='+(new Date(0)).toGMTString(); o.cookieAfterDelete=d.cookie;j.async=1;j.src=r; if(l){l(e,h,false);if(p){l(t,i,false);}}else if(m) {m('on'+e,h);if(p){m('on'+t,i);}} if(o.sync){d.write('<'+s+' src=\\''+r+'\\'></'+s+'>');} else{x.parentNode.insertBefore(j,x);} })();} </script> <script>if(!RVBD_EUE_PARAM){var RVBD_EUE_PARAM={};} RVBD_EUE_PARAM.pageId = 'a2_e6e8c617-d7ec-4acd-a432-08b0febc30e0';</script> <!-- AppInternalsXpert BMX Integration End --> [cadastrado] `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions