JavaScript Reserved Words

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JavaScript has reserved these words for its own use."> <link rel="canonical" href="https://www.quackit.com/javascript/javascript_reserved_words.cfm"> <title>JavaScript Reserved Words</title> <script src="//ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script> <link rel="shortcut icon" href="/pix/favicon96.png"> <link rel="apple-touch-icon" href="/pix/apple-touch-icon.png"> <link rel="preconnect" href="https://fonts.googleapis.com"> <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin> <link href="https://fonts.googleapis.com/css2?family=Lato:ital,wght@0,400;0,700;1,400&display=swap" rel="stylesheet"> <link href="/common/css/master.45.min.css" rel="stylesheet"> <script async src="https://cdn.fuseplatform.net/publift/tags/2/3499/fuse.js"></script>  <script async src="https://www.googletagmanager.com/gtag/js?id=G-Q3H025ZKLN"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); 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value="FORID:10"> <input type="hidden" name="ie" value="ISO-8859-1"> <input type="text" name="q" size="20" class="site-search-input"> <button type="submit" name="sa" class="site-search-button"><i class="fa fa-search"></i></button> </div> </form> </div> </nav> </header> <div class="main"> <article class="content"> <h1 class="page-title">JavaScript Reserved Words</h1> <div class="ad ad-top">  <div data-fuse="23059883623"></div> </div> <p>You should avoid using these reserved words and keywords as function or variable names as <a href="/javascript/">JavaScript</a> has reserved these words for its own use.</p> <div class="ad">  <div data-fuse="23059883629"></div> </div> <table class="tabular col-3"> <tr> <th colspan="3">JavaScript Reserved Words</th> </tr> <tr> <td>break</td> <td>export</td> <td>return</td> </tr> <tr> <td>case</td> <td>for</td> <td>switch</td> </tr> <tr> <td>comment</td> <td>function</td> <td>this</td> </tr> <tr> <td>continue</td> <td>if</td> <td>typeof</td> </tr> <tr> <td>default</td> <td>import</td> <td>var</td> </tr> <tr> <td>delete</td> <td>in</td> <td>void</td> </tr> <tr> <td>do</td> <td>label</td> <td>while</td> </tr> <tr> <td>else</td> <td>new</td> <td>with</td> </tr> </table> <table class="tabular col-3"> <tr> <th colspan="3">Java Keywords (Reserved by JavaScript)</th> </tr> <tr> <td>abstract</td> <td>implements</td> <td>protected</td> </tr> <tr> <td>boolean</td> <td>instanceOf</td> <td>public</td> </tr> <tr> <td>byte</td> <td>int</td> <td>short</td> </tr> <tr> <td>char</td> <td>interface</td> <td>static</td> </tr> <tr> <td>double</td> <td>long</td> <td>synchronized</td> </tr> <tr> <td>false</td> <td>native</td> <td>throws</td> </tr> <tr> <td>final</td> <td>null</td> <td>transient</td> </tr> <tr> <td>float</td> <td>package</td> <td>true</td> </tr> <tr> <td>goto</td> <td>private</td> <td> </td> </tr> </table> <table class="tabular col-3"> <tr> <th colspan="3">ECMAScipt Reserved Words</th> </tr> <tr> <td>catch</td> <td>enum</td> <td>throw</td> </tr> <tr> <td>class</td> <td>extends</td> <td>try</td> </tr> <tr> <td>const</td> <td>finally</td> <td> </td> </tr> <tr> <td>debugger</td> <td>super</td> <td> </td> </tr> </table> <table class="tabular col-3"> <tr> <th colspan="3">Other JavaScript Keywords</th> </tr> <tr> <td>alert</td> <td>isFinite</td> <td>personalbar</td> </tr> <tr> <td>Anchor</td> <td>isNan</td> <td>Plugin</td> </tr> <tr> <td>Area</td> <td>java</td> <td>print</td> </tr> <tr> <td>arguments</td> <td>JavaArray</td> <td>prompt</td> </tr> <tr> <td>Array</td> <td>JavaClass</td> <td>prototype</td> </tr> <tr> <td>assign</td> <td>JavaObject</td> <td>Radio</td> </tr> <tr> <td>blur</td> <td>JavaPackage</td> <td>ref</td> </tr> <tr> <td>Boolean</td> <td>length</td> <td>RegExp</td> </tr> <tr> <td>Button</td> <td>Link</td> <td>releaseEvents</td> </tr> <tr> <td>callee</td> <td>location</td> <td>Reset</td> </tr> <tr> <td>caller</td> <td>Location</td> <td>resizeBy</td> </tr> <tr> <td>captureEvents</td> <td>locationbar</td> <td>resizeTo</td> </tr> <tr> <td>Checkbox</td> <td>Math</td> <td>routeEvent</td> </tr> <tr> <td>clearInterval</td> <td>menubar</td> <td>scroll</td> </tr> <tr> <td>clearTimeout</td> <td>MimeType</td> <td>scrollbars</td> </tr> <tr> <td>close</td> <td>moveBy</td> <td>scrollBy</td> </tr> <tr> <td>closed</td> <td>moveTo</td> <td>scrollTo</td> </tr> <tr> <td>confirm</td> <td>name</td> <td>Select</td> </tr> <tr> <td>constructor</td> <td>NaN</td> <td>self</td> </tr> <tr> <td>Date</td> <td>navigate</td> <td>setInterval</td> </tr> <tr> <td>defaultStatus</td> <td>navigator</td> <td>setTimeout</td> </tr> <tr> <td>document</td> <td>Navigator</td> <td>status</td> </tr> <tr> <td>Document</td> <td>netscape</td> <td>statusbar</td> </tr> <tr> <td>Element</td> <td>Number</td> <td>stop</td> </tr> <tr> <td>escape</td> <td>Object</td> <td>String</td> </tr> <tr> <td>eval</td> <td>onBlur</td> <td>Submit</td> </tr> <tr> <td>FileUpload</td> <td>onError</td> <td>sun</td> </tr> <tr> <td>find</td> <td>onFocus</td> <td>taint</td> </tr> <tr> <td>focus</td> <td>onLoad</td> <td>Text</td> </tr> <tr> <td>Form</td> <td>onUnload</td> <td>Textarea</td> </tr> <tr> <td>Frame</td> <td>open</td> <td>toolbar</td> </tr> <tr> <td>Frames</td> <td>opener</td> <td>top</td> </tr> <tr> <td>Function</td> <td>Option</td> <td>toString</td> </tr> <tr> <td>getClass</td> <td>outerHeight</td> <td>unescape</td> </tr> <tr> <td>Hidden</td> <td>OuterWidth</td> <td>untaint</td> </tr> <tr> <td>history</td> <td>Packages</td> <td>unwatch</td> </tr> <tr> <td>History</td> <td>pageXoffset</td> <td>valueOf</td> </tr> <tr> <td>home</td> <td>pageYoffset</td> <td>watch</td> </tr> <tr> <td>Image</td> <td>parent</td> <td>window</td> </tr> <tr> <td>Infinity</td> <td>parseFloat</td> <td>Window</td> </tr> <tr> <td>InnerHeight</td> <td>parseInt</td> <td> </td> </tr> <tr> <td>InnerWidth</td> <td>Password</td> <td> </td> </tr> </table> </article> <div class="sidebar"> <nav> <ul> <li> <h3><a href="/javascript/tutorial/">JavaScript 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JavaScript Reserved Words