ArrayBuffer.prototype.byteLength - JavaScript | MDN

Try it

// Create an ArrayBuffer with a size in bytes
const buffer = new ArrayBuffer(8);

// Use byteLength to check the size
const bytes = buffer.byteLength;

console.log(bytes);
// Expected output: 8

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

js

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

Specifications

Specification
ECMAScript® 2027 Language Specification
# sec-get-arraybuffer.prototype.bytelength

Browser compatibility

See also

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