Web platform features explorer - Readable byte streams

A ReadableStream constructed with { type: "bytes" } reads bytes from a stream without making extra copies, improving efficiency for streams of large chunks. Also known as BYOB or bring your own buffer.

Status

Baseline Newly Available (since 2026-03-24)

This feature is expected to reach Baseline Widely Available status on: 2028-09-24

MDN documentation

Using readable byte streams

Specifications

Streams, from Streams Workstream (WHATWG).

Browser support (view on caniuse.com)

Chrome 89 Released on 2021-03-02
Chrome Android 89 Released on 2021-03-02
Edge 89 Released on 2021-03-04
Firefox 102 Released on 2022-06-28
Firefox for Android 102 Released on 2022-06-28
Safari 26.4 Released on 2026-03-24
Safari on iOS 26.4 Released on 2026-03-24

Usage (according to Chrome Platform Status)

~0.012% of page loads. More data at chromestatus.com.

Web Platform Tests (WPT)

View the latest WPT test results for this feature

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