Newly availableA strong fit for performance-sensitive binary workflows where copying large buffers would be wasteful.
Language core Newly available

Transferable ArrayBuffer

Transferable ArrayBuffer support allows ownership of a buffer to move without copying the underlying bytes. It is useful when large binary payloads need to move across workers efficiently.

ArrayBufferTransferPerformance

Overview

Transferable ArrayBuffer support allows ownership of a buffer to move without copying the underlying bytes. It is useful when large binary payloads need to move across workers efficiently.

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
javascript.builtins.ArrayBuffer.detached
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122
17.4
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17.4
Built-in object
ArrayBuffer.transfer

The transfer() method of ArrayBuffer instances creates a new ArrayBuffer with the same byte content as this buffer, then detaches this buffer.
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122
17.4
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17.4
ArrayBuffer.transferToFixedLength

The transferToFixedLength() method of ArrayBuffer instances creates a new non-resizable ArrayBuffer with the same byte content as this buffer, then detaches this buffer.
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122
17.4
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17.4
1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
const buf = new ArrayBuffer(1024);
const transferred = buf.transfer();

buf.byteLength;         // 0 (already detached)
transferred.byteLength; // 1024

Live demo

Check transfer support

Inspect whether ArrayBuffer.prototype.transfer exists.

JavaScript
Output
Press the Run button

Transfer a buffer when supported

Move the contents into a new buffer without manual copying.

JavaScript
Output
Press the Run button

Transfer to a fixed size

Use transferToFixedLength when the runtime exposes the helper.

JavaScript
Output
Press the Run button

Use cases

  • Worker handoff

    Move binary data between threads without duplicating the entire payload in memory.

  • Media and file processing

    Pass decoded or transformed buffers through a pipeline while keeping copies to a minimum.

Cautions

  • After transfer, the original owner loses access to the buffer, so lifecycle mistakes can cause confusing bugs.
  • Explicit transfer semantics are powerful, but they demand clear ownership documentation.

Accessibility

  • Faster large-data transfers can help keep document and media processing responsive.
  • User-facing progress still needs to reflect the work happening across thread boundaries.

Related links

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