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aria-label="Expand sidebar" aria-expanded="false" aria-controls="sidebar-quicklinks"><span class="button-wrap"><span class="icon icon-sidebar "></span></span></button><nav class="breadcrumbs-container" aria-label="Breadcrumb"><ol typeof="BreadcrumbList" vocab="https://schema.org/" aria-label="breadcrumbs"><li property="itemListElement" typeof="ListItem"><a href="/en-US/docs/Web" class="breadcrumb" property="item" typeof="WebPage"><span property="name">References</span></a><meta property="position" content="1"/></li><li property="itemListElement" typeof="ListItem"><a href="/en-US/docs/Web/API" class="breadcrumb" property="item" typeof="WebPage"><span property="name">Web APIs</span></a><meta property="position" content="2"/></li><li property="itemListElement" typeof="ListItem"><a href="/en-US/docs/Web/API/Window" class="breadcrumb" property="item" typeof="WebPage"><span property="name">Window</span></a><meta property="position" content="3"/></li><li property="itemListElement" typeof="ListItem"><a href="/en-US/docs/Web/API/Window/setInterval" class="breadcrumb-current-page" property="item" typeof="WebPage"><span property="name">setInterval()</span></a><meta property="position" content="4"/></li></ol></nav><div class="article-actions"><button type="button" class="button action has-icon article-actions-toggle" aria-label="Article actions"><span class="button-wrap"><span class="icon icon-ellipses "></span><span class="article-actions-dialog-heading">Article Actions</span></span></button><ul class="article-actions-entries"><li class="article-actions-entry"><div class="languages-switcher-menu open-on-focus-within"><button id="languages-switcher-button" type="button" class="button action small has-icon languages-switcher-menu" aria-haspopup="menu"><span class="button-wrap"><span class="icon icon-language "></span>English (US)</span></button><div class="hidden"><ul class="submenu language-menu " aria-labelledby="language-menu-button"><li class=" "><form class="submenu-item locale-redirect-setting"><div class="group"><label class="switch"><input type="checkbox" name="locale-redirect"/><span class="slider"></span><span class="label">Remember language</span></label><a href="https://github.com/orgs/mdn/discussions/739" rel="external noopener noreferrer" target="_blank" title="Enable this setting to automatically switch to this language when it's available. (Click to learn more.)"><span class="icon icon-question-mark "></span></a></div></form></li><li class=" "><a data-locale="de" href="/de/docs/Web/API/Window/setInterval" class="button submenu-item"><span>Deutsch</span><span title="Diese Übersetzung ist Teil eines Experiments."><span class="icon icon-experimental "></span></span></a></li><li class=" "><a data-locale="es" href="/es/docs/Web/API/Window/setInterval" class="button submenu-item"><span>Español</span></a></li><li class=" "><a data-locale="ja" href="/ja/docs/Web/API/Window/setInterval" class="button submenu-item"><span>日本語</span></a></li><li class=" "><a data-locale="ko" href="/ko/docs/Web/API/Window/setInterval" class="button submenu-item"><span>한국어</span></a></li><li class=" "><a data-locale="pt-BR" href="/pt-BR/docs/Web/API/Window/setInterval" class="button submenu-item"><span>Português (do Brasil)</span></a></li><li class=" "><a data-locale="ru" href="/ru/docs/Web/API/Window/setInterval" class="button submenu-item"><span>Русский</span></a></li><li class=" "><a data-locale="zh-CN" href="/zh-CN/docs/Web/API/Window/setInterval" class="button submenu-item"><span>中文 (简体)</span></a></li><li class=" "><a data-locale="zh-TW" href="/zh-TW/docs/Web/API/Window/setInterval" class="button submenu-item"><span>正體中文 (繁體)</span></a></li></ul></div></div></li></ul></div></div></div></div><div class="main-wrapper"><div class="sidebar-container"><aside id="sidebar-quicklinks" class="sidebar" data-macro="APIRef"><button type="button" class="button action backdrop" aria-label="Collapse sidebar"><span class="button-wrap"></span></button><nav aria-label="Related Topics" class="sidebar-inner"><header class="sidebar-actions"><section class="sidebar-filter-container"><div class="sidebar-filter "><label id="sidebar-filter-label" class="sidebar-filter-label" for="sidebar-filter-input"><span class="icon icon-filter"></span><span class="visually-hidden">Filter sidebar</span></label><input id="sidebar-filter-input" autoComplete="off" class="sidebar-filter-input-field false" type="text" placeholder="Filter" value=""/><button type="button" class="button action has-icon clear-sidebar-filter-button"><span class="button-wrap"><span class="icon icon-cancel "></span><span class="visually-hidden">Clear filter input</span></span></button></div></section></header><div class="sidebar-inner-nav"><div class="in-nav-toc"><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#syntax">Syntax</a></li><li class="document-toc-item "><a class="document-toc-link" href="#examples">Examples</a></li><li class="document-toc-item "><a class="document-toc-link" href="#the_this_problem">The "this" problem</a></li><li class="document-toc-item "><a class="document-toc-link" href="#usage_notes">Usage notes</a></li><li class="document-toc-item "><a class="document-toc-link" href="#specifications">Specifications</a></li><li class="document-toc-item "><a class="document-toc-link" href="#browser_compatibility">Browser compatibility</a></li><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</a></li></ul></section></div></div><div class="sidebar-body"><ol><li class="section"><a href="/en-US/docs/Web/API/HTML_DOM_API">HTML DOM API</a></li><li class="section"><a href="/en-US/docs/Web/API/Window"><code>Window</code></a></li><li class="toggle"><details open=""><summary>Instance properties</summary><ol><li><a href="/en-US/docs/Web/API/Window/caches"><code>caches</code></a></li><li><a href="/en-US/docs/Web/API/Window/closed"><code>closed</code></a></li><li><a href="/en-US/docs/Web/API/Window/console"><code>console</code></a></li><li><a href="/en-US/docs/Web/API/Window/cookieStore"><code>cookieStore</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/credentialless"><code>credentialless</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/crossOriginIsolated"><code>crossOriginIsolated</code></a></li><li><a href="/en-US/docs/Web/API/Window/crypto"><code>crypto</code></a></li><li><a href="/en-US/docs/Web/API/Window/customElements"><code>customElements</code></a></li><li><a href="/en-US/docs/Web/API/Window/devicePixelRatio"><code>devicePixelRatio</code></a></li><li><a href="/en-US/docs/Web/API/Window/document"><code>document</code></a></li><li><a href="/en-US/docs/Web/API/Window/documentPictureInPicture"><code>documentPictureInPicture</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/event"><code>event</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/external"><code>external</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/fence"><code>fence</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/frameElement"><code>frameElement</code></a></li><li><a href="/en-US/docs/Web/API/Window/frames"><code>frames</code></a></li><li><a href="/en-US/docs/Web/API/Window/fullScreen"><code>fullScreen</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/history"><code>history</code></a></li><li><a href="/en-US/docs/Web/API/Window/indexedDB"><code>indexedDB</code></a></li><li><a href="/en-US/docs/Web/API/Window/innerHeight"><code>innerHeight</code></a></li><li><a href="/en-US/docs/Web/API/Window/innerWidth"><code>innerWidth</code></a></li><li><a href="/en-US/docs/Web/API/Window/isSecureContext"><code>isSecureContext</code></a></li><li><a href="/en-US/docs/Web/API/Window/launchQueue"><code>launchQueue</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/length"><code>length</code></a></li><li><a href="/en-US/docs/Web/API/Window/localStorage"><code>localStorage</code></a></li><li><a href="/en-US/docs/Web/API/Window/location"><code>location</code></a></li><li><a href="/en-US/docs/Web/API/Window/locationbar"><code>locationbar</code></a></li><li><a href="/en-US/docs/Web/API/Window/menubar"><code>menubar</code></a></li><li><a href="/en-US/docs/Web/API/Window/mozInnerScreenX"><code>mozInnerScreenX</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/mozInnerScreenY"><code>mozInnerScreenY</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/name"><code>name</code></a></li><li><a href="/en-US/docs/Web/API/Window/navigation"><code>navigation</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/navigator"><code>navigator</code></a></li><li><a href="/en-US/docs/Web/API/Window/opener"><code>opener</code></a></li><li><a href="/en-US/docs/Web/API/Window/orientation"><code>orientation</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/origin"><code>origin</code></a></li><li><a href="/en-US/docs/Web/API/Window/originAgentCluster"><code>originAgentCluster</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/outerHeight"><code>outerHeight</code></a></li><li><a href="/en-US/docs/Web/API/Window/outerWidth"><code>outerWidth</code></a></li><li><a href="/en-US/docs/Web/API/Window/parent"><code>parent</code></a></li><li><a href="/en-US/docs/Web/API/Window/performance"><code>performance</code></a></li><li><a href="/en-US/docs/Web/API/Window/personalbar"><code>personalbar</code></a></li><li><a href="/en-US/docs/Web/API/Window/scheduler"><code>scheduler</code></a></li><li><a href="/en-US/docs/Web/API/Window/screen"><code>screen</code></a></li><li><a href="/en-US/docs/Web/API/Window/screenLeft"><code>screenLeft</code></a></li><li><a href="/en-US/docs/Web/API/Window/screenTop"><code>screenTop</code></a></li><li><a href="/en-US/docs/Web/API/Window/screenX"><code>screenX</code></a></li><li><a href="/en-US/docs/Web/API/Window/screenY"><code>screenY</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollbars"><code>scrollbars</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollMaxX"><code>scrollMaxX</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/scrollMaxY"><code>scrollMaxY</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/scrollX"><code>scrollX</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollY"><code>scrollY</code></a></li><li><a href="/en-US/docs/Web/API/Window/self"><code>self</code></a></li><li><a href="/en-US/docs/Web/API/Window/sessionStorage"><code>sessionStorage</code></a></li><li><a href="/en-US/docs/Web/API/Window/sharedStorage"><code>sharedStorage</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/speechSynthesis"><code>speechSynthesis</code></a></li><li><a href="/en-US/docs/Web/API/Window/status"><code>status</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/statusbar"><code>statusbar</code></a></li><li><a href="/en-US/docs/Web/API/Window/toolbar"><code>toolbar</code></a></li><li><a href="/en-US/docs/Web/API/Window/top"><code>top</code></a></li><li><a href="/en-US/docs/Web/API/Window/trustedTypes"><code>trustedTypes</code></a></li><li><a href="/en-US/docs/Web/API/Window/visualViewport"><code>visualViewport</code></a></li><li><a href="/en-US/docs/Web/API/Window/window"><code>window</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Instance methods</summary><ol><li><a href="/en-US/docs/Web/API/Window/alert"><code>alert()</code></a></li><li><a href="/en-US/docs/Web/API/Window/atob"><code>atob()</code></a></li><li><a href="/en-US/docs/Web/API/Window/back"><code>back()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/blur"><code>blur()</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/btoa"><code>btoa()</code></a></li><li><a href="/en-US/docs/Web/API/Window/cancelAnimationFrame"><code>cancelAnimationFrame()</code></a></li><li><a href="/en-US/docs/Web/API/Window/cancelIdleCallback"><code>cancelIdleCallback()</code></a></li><li><a href="/en-US/docs/Web/API/Window/captureEvents"><code>captureEvents()</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/clearImmediate"><code>clearImmediate()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/clearInterval"><code>clearInterval()</code></a></li><li><a href="/en-US/docs/Web/API/Window/clearTimeout"><code>clearTimeout()</code></a></li><li><a href="/en-US/docs/Web/API/Window/close"><code>close()</code></a></li><li><a href="/en-US/docs/Web/API/Window/confirm"><code>confirm()</code></a></li><li><a href="/en-US/docs/Web/API/Window/createImageBitmap"><code>createImageBitmap()</code></a></li><li><a href="/en-US/docs/Web/API/Window/dump"><code>dump()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/fetch"><code>fetch()</code></a></li><li><a href="/en-US/docs/Web/API/Window/find"><code>find()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/focus"><code>focus()</code></a></li><li><a href="/en-US/docs/Web/API/Window/forward"><code>forward()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/getComputedStyle"><code>getComputedStyle()</code></a></li><li><a href="/en-US/docs/Web/API/Window/getDefaultComputedStyle"><code>getDefaultComputedStyle()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/getScreenDetails"><code>getScreenDetails()</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/getSelection"><code>getSelection()</code></a></li><li><a href="/en-US/docs/Web/API/Window/matchMedia"><code>matchMedia()</code></a></li><li><a href="/en-US/docs/Web/API/Window/moveBy"><code>moveBy()</code></a></li><li><a href="/en-US/docs/Web/API/Window/moveTo"><code>moveTo()</code></a></li><li><a href="/en-US/docs/Web/API/Window/open"><code>open()</code></a></li><li><a href="/en-US/docs/Web/API/Window/postMessage"><code>postMessage()</code></a></li><li><a href="/en-US/docs/Web/API/Window/print"><code>print()</code></a></li><li><a href="/en-US/docs/Web/API/Window/prompt"><code>prompt()</code></a></li><li><a href="/en-US/docs/Web/API/Window/queryLocalFonts"><code>queryLocalFonts()</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/queueMicrotask"><code>queueMicrotask()</code></a></li><li><a href="/en-US/docs/Web/API/Window/releaseEvents"><code>releaseEvents()</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/reportError"><code>reportError()</code></a></li><li><a href="/en-US/docs/Web/API/Window/requestAnimationFrame"><code>requestAnimationFrame()</code></a></li><li><a href="/en-US/docs/Web/API/Window/requestFileSystem"><code>requestFileSystem()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/requestIdleCallback"><code>requestIdleCallback()</code></a></li><li><a href="/en-US/docs/Web/API/Window/resizeBy"><code>resizeBy()</code></a></li><li><a href="/en-US/docs/Web/API/Window/resizeTo"><code>resizeTo()</code></a></li><li><a href="/en-US/docs/Web/API/Window/scroll"><code>scroll()</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollBy"><code>scrollBy()</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollByLines"><code>scrollByLines()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/scrollByPages"><code>scrollByPages()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/scrollTo"><code>scrollTo()</code></a></li><li><a href="/en-US/docs/Web/API/Window/setImmediate"><code>setImmediate()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><em><code>setInterval()</code> </em></li><li><a href="/en-US/docs/Web/API/Window/setResizable"><code>setResizable()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/setTimeout"><code>setTimeout()</code></a></li><li><a href="/en-US/docs/Web/API/Window/showDirectoryPicker"><code>showDirectoryPicker()</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/showModalDialog"><code>showModalDialog()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/showOpenFilePicker"><code>showOpenFilePicker()</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/showSaveFilePicker"><code>showSaveFilePicker()</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/sizeToContent"><code>sizeToContent()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/stop"><code>stop()</code></a></li><li><a href="/en-US/docs/Web/API/Window/structuredClone"><code>structuredClone()</code></a></li><li><a href="/en-US/docs/Web/API/Window/updateCommands"><code>updateCommands()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/webkitConvertPointFromNodeToPage"><code>webkitConvertPointFromNodeToPage()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/webkitConvertPointFromPageToNode"><code>webkitConvertPointFromPageToNode()</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li></ol></details></li><li class="toggle"><details open=""><summary>Events</summary><ol><li><a href="/en-US/docs/Web/API/Window/afterprint_event"><code>afterprint</code></a></li><li><a href="/en-US/docs/Web/API/Window/appinstalled_event"><code>appinstalled</code></a></li><li><a href="/en-US/docs/Web/API/Window/beforeinstallprompt_event"><code>beforeinstallprompt</code></a></li><li><a href="/en-US/docs/Web/API/Window/beforeprint_event"><code>beforeprint</code></a></li><li><a href="/en-US/docs/Web/API/Window/beforeunload_event"><code>beforeunload</code></a></li><li><a href="/en-US/docs/Web/API/Window/blur_event"><code>blur</code></a></li><li><a href="/en-US/docs/Web/API/Window/copy_event"><code>copy</code></a></li><li><a href="/en-US/docs/Web/API/Window/cut_event"><code>cut</code></a></li><li><a href="/en-US/docs/Web/API/Window/devicemotion_event"><code>devicemotion</code></a></li><li><a href="/en-US/docs/Web/API/Window/deviceorientation_event"><code>deviceorientation</code></a></li><li><a href="/en-US/docs/Web/API/Window/deviceorientationabsolute_event"><code>deviceorientationabsolute</code></a></li><li><a href="/en-US/docs/Web/API/Window/error_event"><code>error</code></a></li><li><a href="/en-US/docs/Web/API/Window/focus_event"><code>focus</code></a></li><li><a href="/en-US/docs/Web/API/Window/gamepadconnected_event"><code>gamepadconnected</code></a></li><li><a href="/en-US/docs/Web/API/Window/gamepaddisconnected_event"><code>gamepaddisconnected</code></a></li><li><a href="/en-US/docs/Web/API/Window/hashchange_event"><code>hashchange</code></a></li><li><a href="/en-US/docs/Web/API/Window/languagechange_event"><code>languagechange</code></a></li><li><a href="/en-US/docs/Web/API/Window/load_event"><code>load</code></a></li><li><a href="/en-US/docs/Web/API/Window/message_event"><code>message</code></a></li><li><a href="/en-US/docs/Web/API/Window/messageerror_event"><code>messageerror</code></a></li><li><a href="/en-US/docs/Web/API/Window/offline_event"><code>offline</code></a></li><li><a href="/en-US/docs/Web/API/Window/online_event"><code>online</code></a></li><li><a href="/en-US/docs/Web/API/Window/orientationchange_event"><code>orientationchange</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/pagehide_event"><code>pagehide</code></a></li><li><a href="/en-US/docs/Web/API/Window/pagereveal_event"><code>pagereveal</code></a></li><li><a href="/en-US/docs/Web/API/Window/pageshow_event"><code>pageshow</code></a></li><li><a href="/en-US/docs/Web/API/Window/pageswap_event"><code>pageswap</code></a></li><li><a href="/en-US/docs/Web/API/Window/paste_event"><code>paste</code></a></li><li><a href="/en-US/docs/Web/API/Window/popstate_event"><code>popstate</code></a></li><li><a href="/en-US/docs/Web/API/Window/rejectionhandled_event"><code>rejectionhandled</code></a></li><li><a href="/en-US/docs/Web/API/Window/resize_event"><code>resize</code></a></li><li><a href="/en-US/docs/Web/API/Window/scrollsnapchange_event"><code>scrollsnapchange</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/scrollsnapchanging_event"><code>scrollsnapchanging</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/storage_event"><code>storage</code></a></li><li><a href="/en-US/docs/Web/API/Window/unhandledrejection_event"><code>unhandledrejection</code></a></li><li><a href="/en-US/docs/Web/API/Window/unload_event"><code>unload</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/vrdisplayactivate_event"><code>vrdisplayactivate</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/vrdisplayconnect_event"><code>vrdisplayconnect</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/vrdisplaydeactivate_event"><code>vrdisplaydeactivate</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/vrdisplaydisconnect_event"><code>vrdisplaydisconnect</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/Window/vrdisplaypresentchange_event"><code>vrdisplaypresentchange</code></a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li></ol></details></li><li class="toggle"><details open=""><summary>Inheritance</summary><ol><li><a href="/en-US/docs/Web/API/EventTarget"><code>EventTarget</code></a></li></ol></details></li><li class="toggle"><details open=""><summary>Related pages for HTML DOM</summary><ol><li><a href="/en-US/docs/Web/API/BeforeUnloadEvent"><code>BeforeUnloadEvent</code></a></li><li><a href="/en-US/docs/Web/API/DOMStringMap"><code>DOMStringMap</code></a></li><li><a href="/en-US/docs/Web/API/ErrorEvent"><code>ErrorEvent</code></a></li><li><a href="/en-US/docs/Web/API/HTMLAnchorElement"><code>HTMLAnchorElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLAreaElement"><code>HTMLAreaElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLAudioElement"><code>HTMLAudioElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLBRElement"><code>HTMLBRElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLBaseElement"><code>HTMLBaseElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLBodyElement"><code>HTMLBodyElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLButtonElement"><code>HTMLButtonElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLCanvasElement"><code>HTMLCanvasElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDListElement"><code>HTMLDListElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDataElement"><code>HTMLDataElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDataListElement"><code>HTMLDataListElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDialogElement"><code>HTMLDialogElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDivElement"><code>HTMLDivElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLDocument"><code>HTMLDocument</code></a></li><li><a href="/en-US/docs/Web/API/HTMLElement"><code>HTMLElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLEmbedElement"><code>HTMLEmbedElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLFieldSetElement"><code>HTMLFieldSetElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLFormControlsCollection"><code>HTMLFormControlsCollection</code></a></li><li><a href="/en-US/docs/Web/API/HTMLFormElement"><code>HTMLFormElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLFrameSetElement"><code>HTMLFrameSetElement</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/HTMLHRElement"><code>HTMLHRElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLHeadElement"><code>HTMLHeadElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLHeadingElement"><code>HTMLHeadingElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLHtmlElement"><code>HTMLHtmlElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLIFrameElement"><code>HTMLIFrameElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLImageElement"><code>HTMLImageElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLInputElement"><code>HTMLInputElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLLIElement"><code>HTMLLIElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLLabelElement"><code>HTMLLabelElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLLegendElement"><code>HTMLLegendElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLLinkElement"><code>HTMLLinkElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLMapElement"><code>HTMLMapElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLMediaElement"><code>HTMLMediaElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLMenuElement"><code>HTMLMenuElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLMetaElement"><code>HTMLMetaElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLMeterElement"><code>HTMLMeterElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLModElement"><code>HTMLModElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLOListElement"><code>HTMLOListElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLObjectElement"><code>HTMLObjectElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLOptGroupElement"><code>HTMLOptGroupElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLOptionElement"><code>HTMLOptionElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLOptionsCollection"><code>HTMLOptionsCollection</code></a></li><li><a href="/en-US/docs/Web/API/HTMLOutputElement"><code>HTMLOutputElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLParagraphElement"><code>HTMLParagraphElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLPictureElement"><code>HTMLPictureElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLPreElement"><code>HTMLPreElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLProgressElement"><code>HTMLProgressElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLQuoteElement"><code>HTMLQuoteElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLScriptElement"><code>HTMLScriptElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLSelectElement"><code>HTMLSelectElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLSourceElement"><code>HTMLSourceElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLSpanElement"><code>HTMLSpanElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLStyleElement"><code>HTMLStyleElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableCaptionElement"><code>HTMLTableCaptionElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableCellElement"><code>HTMLTableCellElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableColElement"><code>HTMLTableColElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableElement"><code>HTMLTableElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableRowElement"><code>HTMLTableRowElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTableSectionElement"><code>HTMLTableSectionElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTemplateElement"><code>HTMLTemplateElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTextAreaElement"><code>HTMLTextAreaElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTimeElement"><code>HTMLTimeElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTitleElement"><code>HTMLTitleElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLTrackElement"><code>HTMLTrackElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLUListElement"><code>HTMLUListElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLUnknownElement"><code>HTMLUnknownElement</code></a></li><li><a href="/en-US/docs/Web/API/HTMLVideoElement"><code>HTMLVideoElement</code></a></li><li><a href="/en-US/docs/Web/API/HashChangeEvent"><code>HashChangeEvent</code></a></li><li><a href="/en-US/docs/Web/API/History"><code>History</code></a></li><li><a href="/en-US/docs/Web/API/ImageData"><code>ImageData</code></a></li><li><a href="/en-US/docs/Web/API/Location"><code>Location</code></a></li><li><a href="/en-US/docs/Web/API/MessageChannel"><code>MessageChannel</code></a></li><li><a href="/en-US/docs/Web/API/MessageEvent"><code>MessageEvent</code></a></li><li><a href="/en-US/docs/Web/API/MessagePort"><code>MessagePort</code></a></li><li><a href="/en-US/docs/Web/API/Navigator"><code>Navigator</code></a></li><li><a href="/en-US/docs/Web/API/PageRevealEvent"><code>PageRevealEvent</code></a></li><li><a href="/en-US/docs/Web/API/PageSwapEvent"><code>PageSwapEvent</code></a></li><li><a href="/en-US/docs/Web/API/PageTransitionEvent"><code>PageTransitionEvent</code></a></li><li><a href="/en-US/docs/Web/API/Plugin"><code>Plugin</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/PluginArray"><code>PluginArray</code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/API/PromiseRejectionEvent"><code>PromiseRejectionEvent</code></a></li><li><a href="/en-US/docs/Web/API/RadioNodeList"><code>RadioNodeList</code></a></li><li><a href="/en-US/docs/Web/API/UserActivation"><code>UserActivation</code></a></li><li><a href="/en-US/docs/Web/API/ValidityState"><code>ValidityState</code></a></li><li><a href="/en-US/docs/Web/API/WorkletGlobalScope"><code>WorkletGlobalScope</code></a></li></ol></details></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#syntax">Syntax</a></li><li class="document-toc-item "><a class="document-toc-link" href="#examples">Examples</a></li><li class="document-toc-item "><a class="document-toc-link" href="#the_this_problem">The "this" problem</a></li><li class="document-toc-item "><a class="document-toc-link" href="#usage_notes">Usage notes</a></li><li class="document-toc-item "><a class="document-toc-link" href="#specifications">Specifications</a></li><li class="document-toc-item "><a class="document-toc-link" href="#browser_compatibility">Browser compatibility</a></li><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>Window: setInterval() method</h1><details class="baseline-indicator high"><summary><span class="indicator" role="img" aria-label="Baseline Check"></span><h2>Baseline <span class="not-bold">Widely available</span></h2><div class="browsers"><span class="engine" title="Supported in Chrome and Edge"><span class="browser chrome supported" role="img" aria-label="Chrome check"></span><span class="browser edge supported" role="img" aria-label="Edge check"></span></span><span class="engine" title="Supported in Firefox"><span class="browser firefox supported" role="img" aria-label="Firefox check"></span></span><span class="engine" title="Supported in Safari"><span class="browser safari supported" role="img" aria-label="Safari check"></span></span></div><span class="icon icon-chevron "></span></summary><div class="extra"><p>This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.</p><ul><li><a href="/en-US/docs/Glossary/Baseline/Compatibility" data-glean="baseline_link_learn_more" target="_blank" class="learn-more">Learn more</a></li><li><a href="#browser_compatibility" data-glean="baseline_link_bcd_table">See full compatibility</a></li><li><a href="https://survey.alchemer.com/s3/7634825/MDN-baseline-feedback?page=%2Fen-US%2Fdocs%2FWeb%2FAPI%2FWindow%2FsetInterval&level=high" data-glean="baseline_link_feedback" class="feedback-link" target="_blank" rel="noreferrer">Report feedback</a></li></ul></div></details></header><div class="section-content"><p>The <strong><code>setInterval()</code></strong> method of the <a href="/en-US/docs/Web/API/Window"><code>Window</code></a> interface repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.</p> <p>This method returns an interval ID which uniquely identifies the interval, so you can remove it later by calling <a href="/en-US/docs/Web/API/Window/clearInterval" title="clearInterval()"><code>clearInterval()</code></a>.</p></div><section aria-labelledby="syntax"><h2 id="syntax"><a href="#syntax">Syntax</a></h2><div class="section-content"><div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>setInterval(code) setInterval(code, delay) setInterval(func) setInterval(func, delay) setInterval(func, delay, arg1) setInterval(func, delay, arg1, arg2) setInterval(func, delay, arg1, arg2, /* …, */ argN) </code></pre></div></div></section><section aria-labelledby="parameters"><h3 id="parameters"><a href="#parameters">Parameters</a></h3><div class="section-content"><dl> <dt id="func"><a href="#func"><code>func</code></a></dt> <dd> <p>A <a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function"><code>function</code></a> to be executed every <code>delay</code> milliseconds. The first execution happens after <code>delay</code> milliseconds.</p> </dd> <dt id="code"><a href="#code"><code>code</code></a></dt> <dd> <p> An optional syntax allows you to include a string instead of a function, which is compiled and executed every <code>delay</code> milliseconds. This syntax is <em>not recommended</em> for the same reasons that make using <a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval"><code>eval()</code></a> a security risk. </p> </dd> <dt id="delay"><a href="#delay"><code>delay</code></a> <span class="badge inline optional">Optional</span></dt> <dd> <p> The time, in milliseconds (thousandths of a second), the timer should delay in between executions of the specified function or code. Defaults to 0 if not specified. See <a href="#delay_restrictions">Delay restrictions</a> below for details on the permitted range of <code>delay</code> values. </p> </dd> <dt id="arg1"><a href="#arg1"><code>arg1</code></a>, …, <code>argN</code> <span class="badge inline optional">Optional</span></dt> <dd> <p>Additional arguments which are passed through to the function specified by <em>func</em> once the timer expires.</p> </dd> </dl></div></section><section aria-labelledby="return_value"><h3 id="return_value"><a href="#return_value">Return value</a></h3><div class="section-content"><p>The returned <code>intervalID</code> is a numeric, non-zero value which identifies the timer created by the call to <code>setInterval()</code>; this value can be passed to <a href="/en-US/docs/Web/API/Window/clearInterval" title="clearInterval()"><code>clearInterval()</code></a> to cancel the interval.</p> <p> It may be helpful to be aware that <code>setInterval()</code> and <a href="/en-US/docs/Web/API/Window/setTimeout" title="setTimeout()"><code>setTimeout()</code></a> share the same pool of IDs, and that <code>clearInterval()</code> and <a href="/en-US/docs/Web/API/Window/clearTimeout" title="clearTimeout()"><code>clearTimeout()</code></a> can technically be used interchangeably. For clarity, however, you should try to always match them to avoid confusion when maintaining your code. </p> <div class="notecard note"> <p> <strong>Note:</strong> The <code>delay</code> argument is converted to a signed 32-bit integer. This effectively limits <code>delay</code> to 2147483647 ms, roughly 24.8 days, since it's specified as a signed integer in the IDL. </p> </div></div></section><section aria-labelledby="examples"><h2 id="examples"><a href="#examples">Examples</a></h2><div class="section-content"></div></section><section aria-labelledby="example_1_basic_syntax"><h3 id="example_1_basic_syntax"><a href="#example_1_basic_syntax">Example 1: Basic syntax</a></h3><div class="section-content"><p>The following example demonstrates <code>setInterval()</code>'s basic syntax.</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>const intervalID = setInterval(myCallback, 500, "Parameter 1", "Parameter 2"); function myCallback(a, b) { // Your code here // Parameters are purely optional. console.log(a); console.log(b); } </code></pre></div></div></section><section aria-labelledby="example_2_alternating_two_colors"><h3 id="example_2_alternating_two_colors"><a href="#example_2_alternating_two_colors">Example 2: Alternating two colors</a></h3><div class="section-content"><p> The following example calls the <code>flashtext()</code> function once a second until the Stop button is pressed. </p> <h4 id="html">HTML</h4> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><div id="my_box"> <h3>Hello World</h3> </div> <button id="start">Start</button> <button id="stop">Stop</button> </code></pre></div> <h4 id="css">CSS</h4> <div class="code-example"><div class="example-header"><span class="language-name">css</span></div><pre class="brush: css notranslate"><code>.go { color: green; } .stop { color: red; } </code></pre></div> <h4 id="javascript">JavaScript</h4> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>// variable to store our intervalID let intervalId; function changeColor() { // check if an interval has already been set up if (!intervalId) { intervalId = setInterval(flashText, 1000); } } function flashText() { const oElem = document.getElementById("my_box"); oElem.className = oElem.className === "go" ? "stop" : "go"; } function stopTextColor() { clearInterval(intervalId); // release our intervalId from the variable intervalId = null; } document.getElementById("start").addEventListener("click", changeColor); document.getElementById("stop").addEventListener("click", stopTextColor); </code></pre></div> <h4 id="result">Result</h4><div class="code-example"><div class="example-header"></div><iframe class="sample-code-frame" title="Example 2: Alternating two colors sample" id="frame_example_2_alternating_two_colors" src="about:blank" data-live-path="/en-US/docs/Web/API/Window/setInterval" data-live-id="example_2_alternating_two_colors" sandbox="allow-same-origin allow-scripts" loading="lazy"></iframe></div></div></section><section aria-labelledby="the_this_problem"><h2 id="the_this_problem"><a href="#the_this_problem">The "this" problem</a></h2><div class="section-content"><p> When you pass a method to <code>setInterval()</code> or any other function, it is invoked with the wrong <a href="/en-US/docs/Web/JavaScript/Reference/Operators/this"><code>this</code></a> value. This problem is explained in detail in the <a href="/en-US/docs/Web/JavaScript/Reference/Operators/this#callbacks">JavaScript reference</a>. </p></div></section><section aria-labelledby="explanation"><h3 id="explanation"><a href="#explanation">Explanation</a></h3><div class="section-content"><p> Code executed by <code>setInterval()</code> runs in a separate execution context than the function from which it was called. As a consequence, the <a href="/en-US/docs/Web/JavaScript/Reference/Operators/this"><code>this</code></a> keyword for the called function is set to the <code>window</code> (or <code>global</code>) object, it is not the same as the <code>this</code> value for the function that called <code>setTimeout</code>. See the following example (which uses <code>setTimeout()</code> instead of <code>setInterval()</code> – the problem, in fact, is the same for both timers): </p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>myArray = ["zero", "one", "two"]; myArray.myMethod = function (sProperty) { alert(arguments.length > 0 ? this[sProperty] : this); }; myArray.myMethod(); // prints "zero,one,two" myArray.myMethod(1); // prints "one" setTimeout(myArray.myMethod, 1000); // prints "[object Window]" after 1 second setTimeout(myArray.myMethod, 1500, "1"); // prints "undefined" after 1.5 seconds // Passing the 'this' object with .call won't work // because this will change the value of this inside setTimeout itself // while we want to change the value of this inside myArray.myMethod. // In fact, it will be an error because setTimeout code expects this to be the window object: setTimeout.call(myArray, myArray.myMethod, 2000); // error: "NS_ERROR_XPC_BAD_OP_ON_WN_PROTO: Illegal operation on WrappedNative prototype object" setTimeout.call(myArray, myArray.myMethod, 2500, 2); // same error </code></pre></div> <p> As you can see there are no ways to pass the <code>this</code> object to the callback function in the legacy JavaScript. </p></div></section><section aria-labelledby="a_possible_solution"><h3 id="a_possible_solution"><a href="#a_possible_solution">A possible solution</a></h3><div class="section-content"><p>All modern JavaScript runtimes (in browsers and elsewhere) support <a href="/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions">arrow functions</a>, with lexical <code>this</code> — allowing us to write <code>setInterval(() => this.myMethod())</code> if we're inside the <code>myArray</code> method.</p> <p>If you need to support IE, use the <a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind"><code>Function.prototype.bind()</code></a> method, which lets you specify the value that should be used as <code>this</code> for all calls to a given function. That lets you easily bypass problems where it's unclear what <code>this</code> will be, depending on the context from which your function was called.</p></div></section><section aria-labelledby="usage_notes"><h2 id="usage_notes"><a href="#usage_notes">Usage notes</a></h2><div class="section-content"><p> The <code>setInterval()</code> function is commonly used to set a delay for functions that are executed again and again, such as animations. You can cancel the interval using <a href="/en-US/docs/Web/API/Window/clearInterval" title="clearInterval()"><code>clearInterval()</code></a>. </p> <p> If you wish to have your function called <em>once</em> after the specified delay, use <a href="/en-US/docs/Web/API/Window/setTimeout" title="setTimeout()"><code>setTimeout()</code></a>. </p></div></section><section aria-labelledby="delay_restrictions"><h3 id="delay_restrictions"><a href="#delay_restrictions">Delay restrictions</a></h3><div class="section-content"><p> It's possible for intervals to be nested; that is, the callback for <code>setInterval()</code> can in turn call <code>setInterval()</code> to start another interval running, even though the first one is still going. To mitigate the potential impact this can have on performance, once intervals are nested beyond five levels deep, the browser will automatically enforce a 4 ms minimum value for the interval. Attempts to specify a value less than 4 ms in deeply-nested calls to <code>setInterval()</code> will be pinned to 4 ms. </p> <p> Browsers may enforce even more stringent minimum values for the interval under some circumstances, although these should not be common. Note also that the actual amount of time that elapses between calls to the callback may be longer than the given <code>delay</code>; see <a href="/en-US/docs/Web/API/Window/setTimeout#reasons_for_delays_longer_than_specified">Reasons for delays longer than specified</a> for examples. </p></div></section><section aria-labelledby="ensure_that_execution_duration_is_shorter_than_interval_frequency"><h3 id="ensure_that_execution_duration_is_shorter_than_interval_frequency"><a href="#ensure_that_execution_duration_is_shorter_than_interval_frequency">Ensure that execution duration is shorter than interval frequency</a></h3><div class="section-content"><p> If there is a possibility that your logic could take longer to execute than the interval time, it is recommended that you recursively call a named function using <a href="/en-US/docs/Web/API/Window/setTimeout" title="setTimeout()"><code>setTimeout()</code></a>. For example, if using <code>setInterval()</code> to poll a remote server every 5 seconds, network latency, an unresponsive server, and a host of other issues could prevent the request from completing in its allotted time. As such, you may find yourself with queued up XHR requests that won't necessarily return in order. </p> <p>In these cases, a recursive <code>setTimeout()</code> pattern is preferred:</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>(function loop() { setTimeout(() => { // Your logic here loop(); }, delay); })(); </code></pre></div> <p> In the above snippet, a named function <code>loop()</code> is declared and is immediately executed. <code>loop()</code> is recursively called inside <code>setTimeout()</code> after the logic has completed executing. While this pattern does not guarantee execution on a fixed interval, it does guarantee that the previous interval has completed before recursing. </p></div></section><h2 id="specifications"><a href="#specifications">Specifications</a></h2><table class="standard-table"><thead><tr><th scope="col">Specification</th></tr></thead><tbody><tr><td><a href="https://html.spec.whatwg.org/multipage/timers-and-user-prompts.html#dom-setinterval-dev">HTML Standard <br/><small># dom-setinterval-dev</small></a></td></tr></tbody></table><h2 id="browser_compatibility"><a href="#browser_compatibility">Browser compatibility</a></h2><p>BCD tables only load in the browser<noscript> with JavaScript enabled. Enable JavaScript to view data.</noscript></p><section aria-labelledby="see_also"><h2 id="see_also"><a href="#see_also">See also</a></h2><div class="section-content"><ul> <li><a href="https://github.com/zloirock/core-js#settimeout-and-setinterval" class="external" target="_blank">Polyfill of <code>setInterval</code> which allows passing arguments to the callback in <code>core-js</code></a></li> <li><a href="/en-US/docs/Web/API/Window/clearInterval"><code>Window.clearInterval()</code></a></li> <li><a href="/en-US/docs/Web/API/WorkerGlobalScope/setInterval"><code>WorkerGlobalScope.setInterval()</code></a></li> <li><a href="/en-US/docs/Web/API/Window/setTimeout"><code>Window.setTimeout()</code></a></li> <li><a href="/en-US/docs/Web/API/Window/requestAnimationFrame"><code>Window.requestAnimationFrame()</code></a></li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" 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2.512 0 4.812 1.522 4.812 4.84v6.402h1.863v3.044h-.005Zm9.036.307c-4.314 0-7.296-2.635-7.296-7.106 0-4.096 2.484-7.481 7.514-7.481s7.481 3.38 7.481 7.29c0 4.472-3.228 7.297-7.699 7.297Zm22.578-.307H51.942l-.403-2.11 7.7-8.846h-4.376l-.621 2.17-2.888-.313.498-4.907h12.294l.313 2.11-7.767 8.852h4.533l.654-2.172 3.167.308-.872 4.908Zm7.99 0h-4.191v-5.03h4.19v5.03Zm0-8.976h-4.191v-5.03h4.19v5.03Zm2.618 8.976 6.054-21.358h3.945l-6.054 21.358h-3.945Zm8.136 0 6.048-21.358h3.945l-6.054 21.358h-3.939Zm21.486.307c-1.863 0-2.887-1.085-3.072-2.792-.805 1.427-2.232 2.792-4.498 2.792-2.02 0-4.314-1.085-4.314-4.006 0-3.447 3.323-4.253 6.518-4.253.778 0 1.584.034 2.3.124v-.465c0-1.427-.034-3.133-2.3-3.133-.84 0-1.488.061-2.143.402l-.453 1.578-3.195-.34.549-3.224c2.45-.996 3.692-1.27 5.992-1.27 3.01 0 5.556 1.55 5.556 4.75v6.083c0 .805.314 1.085.963 1.085.184 0 .375-.034.587-.095l.034 2.11a5.432 5.432 0 0 1-2.524.654Z" fill="currentColor"></path></svg></a><ul class="footer-moz-list"><li 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href="https://foundation.mozilla.org/">Mozilla Foundation</a>.<br/>Portions of this content are ©1998–2024 by individual mozilla.org contributors. Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Web/API/Window/setInterval","doc":{"isMarkdown":true,"isTranslated":false,"isActive":true,"flaws":{},"title":"Window: setInterval() method","mdn_url":"/en-US/docs/Web/API/Window/setInterval","locale":"en-US","native":"English (US)","browserCompat":["api.setInterval"],"baseline":{"baseline":"high","baseline_high_date":"2018-01-29","baseline_low_date":"2015-07-29","support":{"chrome":"1","chrome_android":"18","edge":"12","firefox":"1","firefox_android":"4","safari":"1","safari_ios":"1"}},"sidebarHTML":"<ol><li class=\"section\"><a href=\"/en-US/docs/Web/API/HTML_DOM_API\">HTML DOM API</a></li><li class=\"section\"><a href=\"/en-US/docs/Web/API/Window\"><code>Window</code></a></li><li class=\"toggle\"><details open=\"\"><summary>Instance properties</summary><ol><li><a href=\"/en-US/docs/Web/API/Window/caches\"><code>caches</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/closed\"><code>closed</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/console\"><code>console</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/cookieStore\"><code>cookieStore</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/credentialless\"><code>credentialless</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/crossOriginIsolated\"><code>crossOriginIsolated</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/crypto\"><code>crypto</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/customElements\"><code>customElements</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/devicePixelRatio\"><code>devicePixelRatio</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/document\"><code>document</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/documentPictureInPicture\"><code>documentPictureInPicture</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/event\"><code>event</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/external\"><code>external</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/fence\"><code>fence</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/frameElement\"><code>frameElement</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/frames\"><code>frames</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/fullScreen\"><code>fullScreen</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/history\"><code>history</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/indexedDB\"><code>indexedDB</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/innerHeight\"><code>innerHeight</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/innerWidth\"><code>innerWidth</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/isSecureContext\"><code>isSecureContext</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/launchQueue\"><code>launchQueue</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/length\"><code>length</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/localStorage\"><code>localStorage</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/location\"><code>location</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/locationbar\"><code>locationbar</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/menubar\"><code>menubar</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/mozInnerScreenX\"><code>mozInnerScreenX</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/mozInnerScreenY\"><code>mozInnerScreenY</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/name\"><code>name</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/navigation\"><code>navigation</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/navigator\"><code>navigator</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/opener\"><code>opener</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/orientation\"><code>orientation</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/origin\"><code>origin</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/originAgentCluster\"><code>originAgentCluster</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/outerHeight\"><code>outerHeight</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/outerWidth\"><code>outerWidth</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/parent\"><code>parent</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/performance\"><code>performance</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/personalbar\"><code>personalbar</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scheduler\"><code>scheduler</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/screen\"><code>screen</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/screenLeft\"><code>screenLeft</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/screenTop\"><code>screenTop</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/screenX\"><code>screenX</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/screenY\"><code>screenY</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollbars\"><code>scrollbars</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollMaxX\"><code>scrollMaxX</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/scrollMaxY\"><code>scrollMaxY</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/scrollX\"><code>scrollX</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollY\"><code>scrollY</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/self\"><code>self</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/sessionStorage\"><code>sessionStorage</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/sharedStorage\"><code>sharedStorage</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/speechSynthesis\"><code>speechSynthesis</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/status\"><code>status</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/statusbar\"><code>statusbar</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/toolbar\"><code>toolbar</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/top\"><code>top</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/trustedTypes\"><code>trustedTypes</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/visualViewport\"><code>visualViewport</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/window\"><code>window</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Instance methods</summary><ol><li><a href=\"/en-US/docs/Web/API/Window/alert\"><code>alert()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/atob\"><code>atob()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/back\"><code>back()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/blur\"><code>blur()</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/btoa\"><code>btoa()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/cancelAnimationFrame\"><code>cancelAnimationFrame()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/cancelIdleCallback\"><code>cancelIdleCallback()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/captureEvents\"><code>captureEvents()</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/clearImmediate\"><code>clearImmediate()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/clearInterval\"><code>clearInterval()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/clearTimeout\"><code>clearTimeout()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/close\"><code>close()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/confirm\"><code>confirm()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/createImageBitmap\"><code>createImageBitmap()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/dump\"><code>dump()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/fetch\"><code>fetch()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/find\"><code>find()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/focus\"><code>focus()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/forward\"><code>forward()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/getComputedStyle\"><code>getComputedStyle()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/getDefaultComputedStyle\"><code>getDefaultComputedStyle()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/getScreenDetails\"><code>getScreenDetails()</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/getSelection\"><code>getSelection()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/matchMedia\"><code>matchMedia()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/moveBy\"><code>moveBy()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/moveTo\"><code>moveTo()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/open\"><code>open()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/postMessage\"><code>postMessage()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/print\"><code>print()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/prompt\"><code>prompt()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/queryLocalFonts\"><code>queryLocalFonts()</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/queueMicrotask\"><code>queueMicrotask()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/releaseEvents\"><code>releaseEvents()</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/reportError\"><code>reportError()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/requestAnimationFrame\"><code>requestAnimationFrame()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/requestFileSystem\"><code>requestFileSystem()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/requestIdleCallback\"><code>requestIdleCallback()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/resizeBy\"><code>resizeBy()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/resizeTo\"><code>resizeTo()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scroll\"><code>scroll()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollBy\"><code>scrollBy()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollByLines\"><code>scrollByLines()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/scrollByPages\"><code>scrollByPages()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/scrollTo\"><code>scrollTo()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/setImmediate\"><code>setImmediate()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><em><code>setInterval()</code> </em></li><li><a href=\"/en-US/docs/Web/API/Window/setResizable\"><code>setResizable()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/setTimeout\"><code>setTimeout()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/showDirectoryPicker\"><code>showDirectoryPicker()</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/showModalDialog\"><code>showModalDialog()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/showOpenFilePicker\"><code>showOpenFilePicker()</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/showSaveFilePicker\"><code>showSaveFilePicker()</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/sizeToContent\"><code>sizeToContent()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/stop\"><code>stop()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/structuredClone\"><code>structuredClone()</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/updateCommands\"><code>updateCommands()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/webkitConvertPointFromNodeToPage\"><code>webkitConvertPointFromNodeToPage()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/webkitConvertPointFromPageToNode\"><code>webkitConvertPointFromPageToNode()</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Events</summary><ol><li><a href=\"/en-US/docs/Web/API/Window/afterprint_event\"><code>afterprint</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/appinstalled_event\"><code>appinstalled</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/beforeinstallprompt_event\"><code>beforeinstallprompt</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/beforeprint_event\"><code>beforeprint</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/beforeunload_event\"><code>beforeunload</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/blur_event\"><code>blur</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/copy_event\"><code>copy</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/cut_event\"><code>cut</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/devicemotion_event\"><code>devicemotion</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/deviceorientation_event\"><code>deviceorientation</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/deviceorientationabsolute_event\"><code>deviceorientationabsolute</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/error_event\"><code>error</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/focus_event\"><code>focus</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/gamepadconnected_event\"><code>gamepadconnected</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/gamepaddisconnected_event\"><code>gamepaddisconnected</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/hashchange_event\"><code>hashchange</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/languagechange_event\"><code>languagechange</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/load_event\"><code>load</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/message_event\"><code>message</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/messageerror_event\"><code>messageerror</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/offline_event\"><code>offline</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/online_event\"><code>online</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/orientationchange_event\"><code>orientationchange</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/pagehide_event\"><code>pagehide</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/pagereveal_event\"><code>pagereveal</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/pageshow_event\"><code>pageshow</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/pageswap_event\"><code>pageswap</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/paste_event\"><code>paste</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/popstate_event\"><code>popstate</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/rejectionhandled_event\"><code>rejectionhandled</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/resize_event\"><code>resize</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/scrollsnapchange_event\"><code>scrollsnapchange</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/scrollsnapchanging_event\"><code>scrollsnapchanging</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n <span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/storage_event\"><code>storage</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/unhandledrejection_event\"><code>unhandledrejection</code></a></li><li><a href=\"/en-US/docs/Web/API/Window/unload_event\"><code>unload</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/vrdisplayactivate_event\"><code>vrdisplayactivate</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/vrdisplayconnect_event\"><code>vrdisplayconnect</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/vrdisplaydeactivate_event\"><code>vrdisplaydeactivate</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/vrdisplaydisconnect_event\"><code>vrdisplaydisconnect</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/Window/vrdisplaypresentchange_event\"><code>vrdisplaypresentchange</code></a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Inheritance</summary><ol><li><a href=\"/en-US/docs/Web/API/EventTarget\"><code>EventTarget</code></a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Related pages for HTML DOM</summary><ol><li><a href=\"/en-US/docs/Web/API/BeforeUnloadEvent\"><code>BeforeUnloadEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/DOMStringMap\"><code>DOMStringMap</code></a></li><li><a href=\"/en-US/docs/Web/API/ErrorEvent\"><code>ErrorEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLAnchorElement\"><code>HTMLAnchorElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLAreaElement\"><code>HTMLAreaElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLAudioElement\"><code>HTMLAudioElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLBRElement\"><code>HTMLBRElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLBaseElement\"><code>HTMLBaseElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLBodyElement\"><code>HTMLBodyElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLButtonElement\"><code>HTMLButtonElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLCanvasElement\"><code>HTMLCanvasElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDListElement\"><code>HTMLDListElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDataElement\"><code>HTMLDataElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDataListElement\"><code>HTMLDataListElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDialogElement\"><code>HTMLDialogElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDivElement\"><code>HTMLDivElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLDocument\"><code>HTMLDocument</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLElement\"><code>HTMLElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLEmbedElement\"><code>HTMLEmbedElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLFieldSetElement\"><code>HTMLFieldSetElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLFormControlsCollection\"><code>HTMLFormControlsCollection</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLFormElement\"><code>HTMLFormElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLFrameSetElement\"><code>HTMLFrameSetElement</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/HTMLHRElement\"><code>HTMLHRElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLHeadElement\"><code>HTMLHeadElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLHeadingElement\"><code>HTMLHeadingElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLHtmlElement\"><code>HTMLHtmlElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLIFrameElement\"><code>HTMLIFrameElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLImageElement\"><code>HTMLImageElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLInputElement\"><code>HTMLInputElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLLIElement\"><code>HTMLLIElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLLabelElement\"><code>HTMLLabelElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLLegendElement\"><code>HTMLLegendElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLLinkElement\"><code>HTMLLinkElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLMapElement\"><code>HTMLMapElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLMediaElement\"><code>HTMLMediaElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLMenuElement\"><code>HTMLMenuElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLMetaElement\"><code>HTMLMetaElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLMeterElement\"><code>HTMLMeterElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLModElement\"><code>HTMLModElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLOListElement\"><code>HTMLOListElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLObjectElement\"><code>HTMLObjectElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLOptGroupElement\"><code>HTMLOptGroupElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLOptionElement\"><code>HTMLOptionElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLOptionsCollection\"><code>HTMLOptionsCollection</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLOutputElement\"><code>HTMLOutputElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLParagraphElement\"><code>HTMLParagraphElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLPictureElement\"><code>HTMLPictureElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLPreElement\"><code>HTMLPreElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLProgressElement\"><code>HTMLProgressElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLQuoteElement\"><code>HTMLQuoteElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLScriptElement\"><code>HTMLScriptElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLSelectElement\"><code>HTMLSelectElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLSourceElement\"><code>HTMLSourceElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLSpanElement\"><code>HTMLSpanElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLStyleElement\"><code>HTMLStyleElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableCaptionElement\"><code>HTMLTableCaptionElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableCellElement\"><code>HTMLTableCellElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableColElement\"><code>HTMLTableColElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableElement\"><code>HTMLTableElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableRowElement\"><code>HTMLTableRowElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTableSectionElement\"><code>HTMLTableSectionElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTemplateElement\"><code>HTMLTemplateElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTextAreaElement\"><code>HTMLTextAreaElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTimeElement\"><code>HTMLTimeElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTitleElement\"><code>HTMLTitleElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLTrackElement\"><code>HTMLTrackElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLUListElement\"><code>HTMLUListElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLUnknownElement\"><code>HTMLUnknownElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HTMLVideoElement\"><code>HTMLVideoElement</code></a></li><li><a href=\"/en-US/docs/Web/API/HashChangeEvent\"><code>HashChangeEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/History\"><code>History</code></a></li><li><a href=\"/en-US/docs/Web/API/ImageData\"><code>ImageData</code></a></li><li><a href=\"/en-US/docs/Web/API/Location\"><code>Location</code></a></li><li><a href=\"/en-US/docs/Web/API/MessageChannel\"><code>MessageChannel</code></a></li><li><a href=\"/en-US/docs/Web/API/MessageEvent\"><code>MessageEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/MessagePort\"><code>MessagePort</code></a></li><li><a href=\"/en-US/docs/Web/API/Navigator\"><code>Navigator</code></a></li><li><a href=\"/en-US/docs/Web/API/PageRevealEvent\"><code>PageRevealEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/PageSwapEvent\"><code>PageSwapEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/PageTransitionEvent\"><code>PageTransitionEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/Plugin\"><code>Plugin</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/PluginArray\"><code>PluginArray</code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/API/PromiseRejectionEvent\"><code>PromiseRejectionEvent</code></a></li><li><a href=\"/en-US/docs/Web/API/RadioNodeList\"><code>RadioNodeList</code></a></li><li><a href=\"/en-US/docs/Web/API/UserActivation\"><code>UserActivation</code></a></li><li><a href=\"/en-US/docs/Web/API/ValidityState\"><code>ValidityState</code></a></li><li><a href=\"/en-US/docs/Web/API/WorkletGlobalScope\"><code>WorkletGlobalScope</code></a></li></ol></details></li></ol>","sidebarMacro":"APIRef","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>The <strong><code>setInterval()</code></strong> method of the <a href=\"/en-US/docs/Web/API/Window\"><code>Window</code></a> interface repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.</p>\n<p>This method returns an interval ID which uniquely identifies the interval, so you can remove it later by calling <a href=\"/en-US/docs/Web/API/Window/clearInterval\" title=\"clearInterval()\"><code>clearInterval()</code></a>.</p>"}},{"type":"prose","value":{"id":"syntax","title":"Syntax","isH3":false,"content":"<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>setInterval(code)\nsetInterval(code, delay)\n\nsetInterval(func)\nsetInterval(func, delay)\nsetInterval(func, delay, arg1)\nsetInterval(func, delay, arg1, arg2)\nsetInterval(func, delay, arg1, arg2, /* …, */ argN)\n</code></pre></div>"}},{"type":"prose","value":{"id":"parameters","title":"Parameters","isH3":true,"content":"<dl>\n <dt id=\"func\"><a href=\"#func\"><code>func</code></a></dt>\n <dd>\n <p>A <a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function\"><code>function</code></a> to be executed every <code>delay</code> milliseconds. The first execution happens after <code>delay</code> milliseconds.</p>\n </dd>\n <dt id=\"code\"><a href=\"#code\"><code>code</code></a></dt>\n <dd>\n <p>\n An optional syntax allows you to include a string instead of a function, which is compiled and executed every <code>delay</code> milliseconds.\n This syntax is <em>not recommended</em> for the same reasons that make using <a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval\"><code>eval()</code></a> a security risk.\n </p>\n </dd>\n <dt id=\"delay\"><a href=\"#delay\"><code>delay</code></a> <span class=\"badge inline optional\">Optional</span></dt>\n <dd>\n <p>\n The time, in milliseconds (thousandths of a second), the timer should delay in between executions of the specified function or code. Defaults to 0 if not specified.\n See <a href=\"#delay_restrictions\">Delay restrictions</a> below for details on the permitted range of <code>delay</code> values.\n </p>\n </dd>\n <dt id=\"arg1\"><a href=\"#arg1\"><code>arg1</code></a>, …, <code>argN</code> <span class=\"badge inline optional\">Optional</span></dt>\n <dd>\n <p>Additional arguments which are passed through to the function specified by <em>func</em> once the timer expires.</p>\n </dd>\n</dl>"}},{"type":"prose","value":{"id":"return_value","title":"Return value","isH3":true,"content":"<p>The returned <code>intervalID</code> is a numeric, non-zero value which identifies the timer created by the call to <code>setInterval()</code>; this value can be passed to <a href=\"/en-US/docs/Web/API/Window/clearInterval\" title=\"clearInterval()\"><code>clearInterval()</code></a> to cancel the interval.</p>\n<p>\n It may be helpful to be aware that <code>setInterval()</code> and <a href=\"/en-US/docs/Web/API/Window/setTimeout\" title=\"setTimeout()\"><code>setTimeout()</code></a> share the same pool of IDs, and that <code>clearInterval()</code> and <a href=\"/en-US/docs/Web/API/Window/clearTimeout\" title=\"clearTimeout()\"><code>clearTimeout()</code></a> can technically be used interchangeably.\n For clarity, however, you should try to always match them to avoid confusion when maintaining your code.\n</p>\n<div class=\"notecard note\">\n <p>\n <strong>Note:</strong> The <code>delay</code> argument is converted to a signed 32-bit integer.\n This effectively limits <code>delay</code> to 2147483647 ms, roughly 24.8 days, since it's specified as a signed integer in the IDL.\n </p>\n</div>"}},{"type":"prose","value":{"id":"examples","title":"Examples","isH3":false,"content":""}},{"type":"prose","value":{"id":"example_1_basic_syntax","title":"Example 1: Basic syntax","isH3":true,"content":"<p>The following example demonstrates <code>setInterval()</code>'s basic syntax.</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>const intervalID = setInterval(myCallback, 500, \"Parameter 1\", \"Parameter 2\");\n\nfunction myCallback(a, b) {\n // Your code here\n // Parameters are purely optional.\n console.log(a);\n console.log(b);\n}\n</code></pre></div>"}},{"type":"prose","value":{"id":"example_2_alternating_two_colors","title":"Example 2: Alternating two colors","isH3":true,"content":"<p>\n The following example calls the <code>flashtext()</code> function once a second until\n the Stop button is pressed.\n</p>\n<h4 id=\"html\">HTML</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><div id=\"my_box\">\n <h3>Hello World</h3>\n</div>\n<button id=\"start\">Start</button>\n<button id=\"stop\">Stop</button>\n</code></pre></div>\n<h4 id=\"css\">CSS</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">css</span></div><pre class=\"brush: css notranslate\"><code>.go {\n color: green;\n}\n.stop {\n color: red;\n}\n</code></pre></div>\n<h4 id=\"javascript\">JavaScript</h4>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>// variable to store our intervalID\nlet intervalId;\n\nfunction changeColor() {\n // check if an interval has already been set up\n if (!intervalId) {\n intervalId = setInterval(flashText, 1000);\n }\n}\n\nfunction flashText() {\n const oElem = document.getElementById(\"my_box\");\n oElem.className = oElem.className === \"go\" ? \"stop\" : \"go\";\n}\n\nfunction stopTextColor() {\n clearInterval(intervalId);\n // release our intervalId from the variable\n intervalId = null;\n}\n\ndocument.getElementById(\"start\").addEventListener(\"click\", changeColor);\ndocument.getElementById(\"stop\").addEventListener(\"click\", stopTextColor);\n</code></pre></div>\n<h4 id=\"result\">Result</h4><div class=\"code-example\"><div class=\"example-header\"></div><iframe class=\"sample-code-frame\" title=\"Example 2: Alternating two colors sample\" id=\"frame_example_2_alternating_two_colors\" src=\"about:blank\" data-live-path=\"/en-US/docs/Web/API/Window/setInterval\" data-live-id=\"example_2_alternating_two_colors\" sandbox=\"allow-same-origin allow-scripts\" loading=\"lazy\"></iframe></div>"}},{"type":"prose","value":{"id":"the_this_problem","title":"The \"this\" problem","isH3":false,"content":"<p>\n When you pass a method to <code>setInterval()</code> or any other function, it is invoked with the wrong <a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/this\"><code>this</code></a> value.\n This problem is explained in detail in the <a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/this#callbacks\">JavaScript reference</a>.\n</p>"}},{"type":"prose","value":{"id":"explanation","title":"Explanation","isH3":true,"content":"<p>\n Code executed by <code>setInterval()</code> runs in a separate execution context than\n the function from which it was called. As a consequence, the <a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/this\"><code>this</code></a>\n keyword for the called function is set to the <code>window</code> (or\n <code>global</code>) object, it is not the same as the <code>this</code> value for the\n function that called <code>setTimeout</code>. See the following example (which uses\n <code>setTimeout()</code> instead of <code>setInterval()</code> – the problem, in fact,\n is the same for both timers):\n</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>myArray = [\"zero\", \"one\", \"two\"];\n\nmyArray.myMethod = function (sProperty) {\n alert(arguments.length > 0 ? this[sProperty] : this);\n};\n\nmyArray.myMethod(); // prints \"zero,one,two\"\nmyArray.myMethod(1); // prints \"one\"\nsetTimeout(myArray.myMethod, 1000); // prints \"[object Window]\" after 1 second\nsetTimeout(myArray.myMethod, 1500, \"1\"); // prints \"undefined\" after 1.5 seconds\n\n// Passing the 'this' object with .call won't work\n// because this will change the value of this inside setTimeout itself\n// while we want to change the value of this inside myArray.myMethod.\n// In fact, it will be an error because setTimeout code expects this to be the window object:\nsetTimeout.call(myArray, myArray.myMethod, 2000); // error: \"NS_ERROR_XPC_BAD_OP_ON_WN_PROTO: Illegal operation on WrappedNative prototype object\"\nsetTimeout.call(myArray, myArray.myMethod, 2500, 2); // same error\n</code></pre></div>\n<p>\n As you can see there are no ways to pass the <code>this</code> object to the callback\n function in the legacy JavaScript.\n</p>"}},{"type":"prose","value":{"id":"a_possible_solution","title":"A possible solution","isH3":true,"content":"<p>All modern JavaScript runtimes (in browsers and elsewhere) support <a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions\">arrow functions</a>, with lexical <code>this</code> — allowing us to write <code>setInterval(() => this.myMethod())</code> if we're inside the <code>myArray</code> method.</p>\n<p>If you need to support IE, use the <a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind\"><code>Function.prototype.bind()</code></a> method, which lets you specify the value that should be used as <code>this</code> for all calls to a given function. That lets you easily bypass problems where it's unclear what <code>this</code> will be, depending on the context from which your function was called.</p>"}},{"type":"prose","value":{"id":"usage_notes","title":"Usage notes","isH3":false,"content":"<p>\n The <code>setInterval()</code> function is commonly used to set a delay for functions\n that are executed again and again, such as animations. You can cancel the interval using\n <a href=\"/en-US/docs/Web/API/Window/clearInterval\" title=\"clearInterval()\"><code>clearInterval()</code></a>.\n</p>\n<p>\n If you wish to have your function called <em>once</em> after the specified delay, use\n <a href=\"/en-US/docs/Web/API/Window/setTimeout\" title=\"setTimeout()\"><code>setTimeout()</code></a>.\n</p>"}},{"type":"prose","value":{"id":"delay_restrictions","title":"Delay restrictions","isH3":true,"content":"<p>\n It's possible for intervals to be nested; that is, the callback for\n <code>setInterval()</code> can in turn call <code>setInterval()</code> to start another\n interval running, even though the first one is still going. To mitigate the potential\n impact this can have on performance, once intervals are nested beyond five levels deep,\n the browser will automatically enforce a 4 ms minimum value for the interval. Attempts\n to specify a value less than 4 ms in deeply-nested calls to <code>setInterval()</code>\n will be pinned to 4 ms.\n</p>\n<p>\n Browsers may enforce even more stringent minimum values for the interval under some\n circumstances, although these should not be common. Note also that the actual amount of\n time that elapses between calls to the callback may be longer than the given\n <code>delay</code>; see\n <a href=\"/en-US/docs/Web/API/Window/setTimeout#reasons_for_delays_longer_than_specified\">Reasons for delays longer than specified</a> for examples.\n</p>"}},{"type":"prose","value":{"id":"ensure_that_execution_duration_is_shorter_than_interval_frequency","title":"Ensure that execution duration is shorter than interval frequency","isH3":true,"content":"<p>\n If there is a possibility that your logic could take longer to execute than the\n interval time, it is recommended that you recursively call a named function using\n <a href=\"/en-US/docs/Web/API/Window/setTimeout\" title=\"setTimeout()\"><code>setTimeout()</code></a>. For example, if\n using <code>setInterval()</code> to poll a remote server every 5 seconds, network\n latency, an unresponsive server, and a host of other issues could prevent the request\n from completing in its allotted time. As such, you may find yourself with queued up XHR\n requests that won't necessarily return in order.\n</p>\n<p>In these cases, a recursive <code>setTimeout()</code> pattern is preferred:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>(function loop() {\n setTimeout(() => {\n // Your logic here\n\n loop();\n }, delay);\n})();\n</code></pre></div>\n<p>\n In the above snippet, a named function <code>loop()</code> is declared and is\n immediately executed. <code>loop()</code> is recursively called inside\n <code>setTimeout()</code> after the logic has completed executing. While this pattern\n does not guarantee execution on a fixed interval, it does guarantee that the previous\n interval has completed before recursing.\n</p>"}},{"type":"specifications","value":{"title":"Specifications","id":"specifications","isH3":false,"specifications":[{"bcdSpecificationURL":"https://html.spec.whatwg.org/multipage/timers-and-user-prompts.html#dom-setinterval-dev","title":"HTML Standard"}],"query":"api.setInterval"}},{"type":"browser_compatibility","value":{"title":"Browser compatibility","id":"browser_compatibility","isH3":false,"query":"api.setInterval"}},{"type":"prose","value":{"id":"see_also","title":"See also","isH3":false,"content":"<ul>\n <li><a href=\"https://github.com/zloirock/core-js#settimeout-and-setinterval\" class=\"external\" target=\"_blank\">Polyfill of <code>setInterval</code> which allows passing arguments to the callback in <code>core-js</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/Window/clearInterval\"><code>Window.clearInterval()</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/WorkerGlobalScope/setInterval\"><code>WorkerGlobalScope.setInterval()</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/Window/setTimeout\"><code>Window.setTimeout()</code></a></li>\n <li><a href=\"/en-US/docs/Web/API/Window/requestAnimationFrame\"><code>Window.requestAnimationFrame()</code></a></li>\n</ul>"}}],"toc":[{"text":"Syntax","id":"syntax"},{"text":"Examples","id":"examples"},{"text":"The \"this\" problem","id":"the_this_problem"},{"text":"Usage notes","id":"usage_notes"},{"text":"Specifications","id":"specifications"},{"text":"Browser compatibility","id":"browser_compatibility"},{"text":"See also","id":"see_also"}],"summary":"The setInterval() method of the Window interface repeatedly calls a function or executes a code snippet, with a fixed time delay between each call.","popularity":0.002,"modified":"2024-10-16T07:58:28.000Z","other_translations":[{"locale":"de","title":"Window: setInterval() Methode","native":"Deutsch"},{"locale":"es","title":"setInterval()","native":"Español"},{"locale":"ja","title":"Window: setInterval() メソッド","native":"日本語"},{"locale":"ko","title":"setInterval()","native":"한국어"},{"locale":"pt-BR","title":"WindowOrWorkerGlobalScope.setInterval()","native":"Português (do Brasil)"},{"locale":"ru","title":"Глобальная функция setInterval()","native":"Русский"},{"locale":"zh-CN","title":"Window：setInterval() 方法","native":"中文 (简体)"},{"locale":"zh-TW","title":"Window：setInterval() 方法","native":"正體中文 (繁體)"}],"pageType":"web-api-instance-method","source":{"folder":"en-us/web/api/window/setinterval","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/api/window/setinterval/index.md","last_commit_url":"https://github.com/mdn/content/commit/00f46adb5616d826821d63b11eac285faf1cf4a5","filename":"index.md"},"short_title":"setInterval()","parents":[{"uri":"/en-US/docs/Web","title":"References"},{"uri":"/en-US/docs/Web/API","title":"Web APIs"},{"uri":"/en-US/docs/Web/API/Window","title":"Window"},{"uri":"/en-US/docs/Web/API/Window/setInterval","title":"setInterval()"}],"pageTitle":"Window: setInterval() method - Web APIs | MDN","noIndexing":false}}</script></body></html>