ArrayBuffer() constructor

The ArrayBuffer() constructor creates ArrayBuffer objects.

Try it

Syntax

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

Note: ArrayBuffer() can only be constructed with new. Attempting to call it without new throws a TypeError.

Parameters

length

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

options Optional Experimental

An object, which can contain the following properties:

maxByteLength Optional Experimental

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 if one of the following is true:

  • 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 a 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);

Note: It is recommended that maxByteLength is set to the smallest value possible for your use case. It should never exceed 1073741824 (1GB) to reduce the risk of out-of-memory errors.

Specifications

Specification
ECMAScript Language Specification
# sec-arraybuffer-constructor

Browser compatibility

BCD tables only load in the browser

See also