Web/JavaScript/Reference/Global objects/ArrayBuffer/byteLength

The byteLength accessor property represents the length of an ArrayBuffer in bytes.

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Description

The byteLength property is an accessor property whose set accessor function is undefined, meaning that you can only read this property. The value is established when the array is constructed and cannot be changed. This property returns 0 if this ArrayBuffer has been detached.

Examples

Using byteLength

var buffer = new ArrayBuffer(8);
buffer.byteLength; // 8

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'ArrayBuffer.prototype.byteLength' in that specification.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
byteLength	Chrome Full support 7	Edge Full support 12	Firefox Full support 4	IE Full support 10	Opera Full support 11.6	Safari Full support 5.1	WebView Android Full support 4	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 12	Safari iOS Full support 4.2	Samsung Internet Android Full support 1.0	nodejs Full support 0.10

Legend

Full support  

Full support

See also

• ArrayBuffer

ArrayBuffer.prototype.byteLength by Mozilla Contributors is licensed under CC-BY-SA 2.5.