SharedArrayBuffer and AtomicsBaseline · Widely available

The SharedArrayBuffer object represents bytes shared between multiple workers and the main thread. The Atomics object safely accesses SharedArrayBuffer data to make sure predictable values are read and written and that operations are not interrupted.

Supported in all major browsers for at least 30 months — safe to use without fallbacks. Baseline since Dec 13, 2021. Widely available since Jun 13, 2024.

How to use ↓Compare browsers

Browser support

DesktopChrome

1–67Not supported

68+Supportedsince Jul 24, 2018

Current: 155

Edge

12–18Not supported

79+Supportedsince Jan 15, 2020

Current: 154

Firefox

1–78Not supported

79+Supportedsince Jul 28, 2020

Current: 157

Safari

1–15.1Not supported

15.2+Supportedsince Dec 13, 2021

Current: 27

MobileChrome Android

18–88Not supported

89+Supportedsince Mar 2, 2021

Current: 155

Firefox Android

4–68Not supported

79+Supportedsince Jul 28, 2020

Current: 157

Safari iOS

1–15.1Not supported

15.2+Supportedsince Dec 13, 2021

Current: 27

How to use

This feature is Baseline widely available — use it freely, no fallback needed.

Example

Full syntax and examples are on MDN: Atomics.

Feature detection

JS · check before using

if (typeof SharedArrayBuffer !== "undefined") {
  // SharedArrayBuffer is available
}

Documentation (MDN)

Specification

Usage share

caniuse.com/sharedarraybuffer ↗

Sub-features

Support for each part of the feature (20). The overall table above shows when the whole feature works.

Sub-feature	Chrome	Edge	Firefox	Safari	Chrome Android	Firefox Android	Safari iOS
Atomics	68	79	78	15.2	89	79	15.2
Atomics.Atomic_operations_on_non_shared_buffers	✕	✕	79	✕	✕	79	✕
Atomics.add	68	79	78	15.2	89	79	15.2
Atomics.and	68	79	78	15.2	89	79	15.2
Atomics.compareExchange	68	79	78	15.2	89	79	15.2
Atomics.exchange	68	79	78	15.2	89	79	15.2
Atomics.isLockFree	68	79	78	15.2	89	79	15.2
Atomics.load	68	79	78	15.2	89	79	15.2
Atomics.notify	68	79	78	15.2	89	79	15.2
Atomics.or	68	79	78	15.2	89	79	15.2
Atomics.store	68	79	78	15.2	89	79	15.2
Atomics.sub	68	79	78	15.2	89	79	15.2
Atomics.wait	68	79	78	15.2	89	79	15.2
Atomics.xor	68	79	78	15.2	89	79	15.2
DataView.DataView.sharedarraybuffer_support	68	79	79	15.2	89	79	15.2
SharedArrayBuffer	68	79	79	15.2	89	79	15.2
SharedArrayBuffer.@@species	68	79	79	15.2	89	79	15.2
SharedArrayBuffer.SharedArrayBuffer	68	79	79	15.2	89	79	15.2
SharedArrayBuffer.byteLength	68	79	79	15.2	89	79	15.2
SharedArrayBuffer.slice	68	79	79	15.2	89	79	15.2