DataView.prototype.byteOffset

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The byteOffset accessor property of DataView instances returns the offset (in bytes) of this view from the start of its ArrayBuffer or SharedArrayBuffer.

Try it

// Create an ArrayBuffer with a size in bytes
const buffer = new ArrayBuffer(16);

const view = new DataView(buffer, 12, 4); // From byte 12 for the next 4 bytes

console.log(view.byteOffset);
// Expected output: 12

Description

The byteOffset property is an accessor property whose set accessor function is undefined, meaning that you can only read this property. The value is established when an DataView is constructed and cannot be changed.

Examples

Using the byteOffset property

js
const buffer = new ArrayBuffer(8);
const dataview = new DataView(buffer);
dataview.byteOffset; // 0 (no offset specified)

const dataview2 = new DataView(buffer, 3);
dataview2.byteOffset; // 3 (as specified when constructing the DataView)

Specifications

Specification
ECMAScript® 2025 Language Specification
# sec-get-dataview.prototype.byteoffset

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
byteOffset

Legend

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Full support
Full support

See also