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

Generated Code

const regex = /(<(?:(?:(?:(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)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(<(?:(?:(?:(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)', 'gm') const str = `<body class="mediawiki querry ltr sitedir-ltr ns-0 ns-subject page-International_English_Language_Testing_System skin-vector action-view vector-animateLayout"> <div id="mw-page-base" class="noprint"></div> <div id="mw-head-base" class="noprint"></div> <div id="content" class="mw-body" role="main"> <a id="top"></a> and also a normal querry <div id="siteNotice"><!-- CentralNotice --></div> <h1 id="firstHeading" class="firstHeading" lang="en"><span dir="auto">International English Language Testing System</span></h1> <div id="bodyContent" class="mw-body-content"> <div id="siteSub">From Wikipedia, the free encyclopedia</div> <div id="contentSub">  (Redirected from <a href="/w/index.php?title=IELTS&amp;redirect=no" title="IELTS">IELTS</a>)</div> <div id="jump-to-nav" class="mw-jump"> Jump to: <a href="#mw-navigation">navigation</a>, <a href="#p-search">search</a> </div> <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;"> <caption class="summary">International English Language Testing System</caption> <tr> <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> </tr> <tr> <th scope="row" style="text-align:left;">Acronym</th> <td>IELTS</td> </tr> <tr> <th scope="row" style="text-align:left;">Type</th> <td>Standardized test. Available in 2 versions: "Academic" and "General training".</td> </tr> <tr> <th scope="row" style="text-align:left;">Developer / administrator</th> <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> </tr> <tr> <th scope="row" style="text-align:left;">Knowledge/skill(s) tested</th> <td>Listening, reading, writing and speaking of the <a href="/wiki/English_language" title="English language">English language</a>.</td> </tr> <tr> <th scope="row" style="text-align:left;">Purpose</th> <td>To assess the English language proficiency of non-native English speakers.</td> </tr> `; // 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