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Document: body property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since May 2018.
The Document.body property represents the
<body> or <frameset> node of the current document, or
null if no such element exists.
js
// Given this HTML: <body id="oldBodyElement"></body>
alert(document.body.id); // "oldBodyElement"
const newBodyElement = document.createElement("body");
newBodyElement.id = "newBodyElement";
document.body = newBodyElement;
alert(document.body.id); // "newBodyElement"
document.body is the element that contains the content for the document.
In documents with <body> contents, returns the
<body> element, and in frameset documents, this returns the outermost
<frameset> element.
Though the body property is settable, setting a new body on a document
will effectively remove all the current children of the existing
<body> element.