ArrayBuffer() constructor

Try it

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

console.log(buffer.byteLength);
// Expected output: 8

Syntax

new ArrayBuffer(length)
new ArrayBuffer(length, options)

Parameters

length

The size, in bytes, of the array buffer to create.

options Optional

An object, which can contain the following properties:

maxByteLength Optional

The maximum size, in bytes, that the array buffer can be resized to.

Return value

A new ArrayBuffer object of the specified size, with its maxByteLength property set to the specified maxByteLength if one was specified. Its contents are initialized to 0.

Exceptions

RangeError

Thrown in one of the following cases:

• length or maxByteLength is larger than Number.MAX_SAFE_INTEGER (≥ 2⁵³) or negative.
• length is larger than maxByteLength.

Examples

Creating an ArrayBuffer

In this example, we create a 8-byte buffer with an Int32Array view referring to the buffer:

const buffer = new ArrayBuffer(8);
const view = new Int32Array(buffer);

Creating a resizable ArrayBuffer

In this example, we create a 8-byte buffer that is resizable to a max length of 16 bytes, then resize() it to 12 bytes:

const buffer = new ArrayBuffer(8, { maxByteLength: 16 });

buffer.resize(12);

Specifications

Browser compatibility

See also

• Polyfill of ArrayBuffer in core-js
• JavaScript typed arrays guide
• SharedArrayBuffer