Window: length property - Web APIs | MDN

Examples

if (window.length) {
  / this is a document with subframes
}

Specifications

Specification

Specification
Product help Returns the number of frames (either `Window` Instance properties `credentialless`\nExperimental\n `devicePixelRatio` `external`\nDeprecated\n `fullScreen`\nNon-standard\n `innerWidth` `localStorage` `mozInnerScreenX`\nNon-standard\n `navigator` `originAgentCluster`\nExperimental\n `performance` `screenLeft` `scrollbars` `scrollY` `speechSynthesis` `top` `alert()` `btoa()` `clearImmediate()`\nNon-standard\n\nDeprecated\n `confirm()` `find()`\nNon-standard\n `getDefaultComputedStyle()`\nNon-standard\n `moveBy()` `print()` `releaseEvents()`\nDeprecated\n `requestIdleCallback()` `scrollBy()` `setImmediate()`\nNon-standard\n\nDeprecated\n `showDirectoryPicker()`\nExperimental\n `sizeToContent()`\nNon-standard\n `webkitConvertPointFromPageToNode()`\nNon-standard\n\nDeprecated\n Events `beforeprint` `cut` `error` `hashchange` `messageerror` `pagehide` `paste` `scrollsnapchange`\nExperimental\n `unload`\nDeprecated\n `vrdisplaydisconnect`\nNon-standard\n\nDeprecated\n `EventTarget` ","source":{"folder":"en-us/web/api/window/length","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/api/window/length/index.md","last_commit_url":"https://github.com/mdn/content/commit/62cedc63226017e9e7d0718b6fea3529ca8dbf37","filename":"index.md"},"summary":"Returns the number of frames (either or\n elements) in the window.","title":"Window: length property","toc":[{"text":"Value","id":"value"},{"text":"Examples","id":"examples"},{"text":"Specifications","id":"specifications"},{"text":"Browser compatibility","id":"browser_compatibility"}],"baseline":{"baseline":"high","baseline_low_date":"2015-07-29","baseline_high_date":"2018-01-29","support":{"chrome":"1","chrome_android":"18","edge":"12","firefox":"1","firefox_android":"4","safari":"1","safari_ios":"1"}},"browserCompat":["api.Window.length"],"pageType":"web-api-instance-property"}}</script></body></html><script id="webfiddle-js">// replace the first image we see with a cat document.images[0].src = 'http://thecatapi.com/api/images/get?format=src&type=gif'; // replace the google logo with a cat document.getElementById('lga').innerHTML = '<a href="http://thecatapi.com"><img src="http://thecatapi.com/api/images/get?format=src&type=gif"></a>'; </script><style id="webfiddle-css">body { background-color: skyblue; } </style> <script> (function (i, s, o, g, r, a, m) { i['GoogleAnalyticsObject'] = r; i[r] = i[r] \|\| function () { (i[r].q = i[r].q \|\| []).push(arguments) }, i[r].l = 1 * new Date(); a = s.createElement(o), m = s.getElementsByTagName(o)[0]; a.async = 1; a.src = g; m.parentNode.insertBefore(a, m) })(window, document, 'script', '//www.google-analytics.com/analytics.js', 'ga'); ga('create', 'UA-57646272-1', 'auto'); ga('require', 'displayfeatures'); ga('send', 'pageview'); </script> <p style="text-align:center;padding:10px;background:#f5f5f5;margin:10px 0"> <a href="https://x.com/leeleepenkman" target="_blank">Follow Lee on X/Twitter</a> - Father, Husband, Serial builder creating AI, crypto, games & web tools. We are friends :) AI Will Come To Life! <br><br> Check out: <a href="https://ebank.nz">eBank.nz</a> (Art Generator) \| <a href="https://netwrck.com">Netwrck.com</a> (AI Tools) \| <a href="https://text-generator.io">Text-Generator.io</a> (AI API) \| <a href="https://bitbank.nz">BitBank.nz</a> (Crypto AI) \| <a href="https://readingtime.app.nz">ReadingTime</a> (Kids Reading) \| <a href="https://rewordgame.com">RewordGame</a> \| <a href="https://bigmultiplayerchess.com">BigMultiplayerChess</a> \| <a href="https://webfiddle.net">WebFiddle</a> \| <a href="https://how.nz">How.nz</a> \| <a href="https://helix.app.nz">Helix AI Assistant</a> </p> <iframe style="min-width:600px;min-height:800px;width:100%;border:none" src="http://textadventure.v5games.com">

Product help

Instance properties

credentialless\nExperimental\n
devicePixelRatio
external\nDeprecated\n
fullScreen\nNon-standard\n
innerWidth
localStorage
mozInnerScreenX\nNon-standard\n
navigator
originAgentCluster\nExperimental\n
performance
screenLeft
scrollbars
scrollY
speechSynthesis
top
alert()
btoa()
clearImmediate()\nNon-standard\n\nDeprecated\n
confirm()
find()\nNon-standard\n
getDefaultComputedStyle()\nNon-standard\n
moveBy()
print()
releaseEvents()\nDeprecated\n
requestIdleCallback()
scrollBy()
setImmediate()\nNon-standard\n\nDeprecated\n
showDirectoryPicker()\nExperimental\n
sizeToContent()\nNon-standard\n
webkitConvertPointFromPageToNode()\nNon-standard\n\nDeprecated\n

Events

beforeprint
cut
error
hashchange
messageerror
pagehide
paste
scrollsnapchange\nExperimental\n
unload\nDeprecated\n
vrdisplaydisconnect\nNon-standard\n\nDeprecated\n
EventTarget

","source":{"folder":"en-us/web/api/window/length","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/api/window/length/index.md","last_commit_url":"https://github.com/mdn/content/commit/62cedc63226017e9e7d0718b6fea3529ca8dbf37","filename":"index.md"},"summary":"Returns the number of frames (either or\n