SharedArrayBuffer.prototype.byteLength

Baseline Widely available

This feature is well established and works across many devices and browser versions. It's been available across browsers since December 2021.

The byteLength accessor property of SharedArrayBuffer instances returns the length (in bytes) of this SharedArrayBuffer.

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 shared array is constructed and cannot be changed.

Examples

Note that these examples cannot be run directly from the console or an arbitrary web page, because SharedArrayBuffer is not defined unless its security requirements are met.

Using byteLength

const sab = new SharedArrayBuffer(1024);
sab.byteLength; // 1024

Specifications

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

Browser compatibility