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The byteLength accessor property represents the length of an ArrayBuffer in bytes.




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 array is constructed and cannot be changed. This property returns 0 if this ArrayBuffer has been detached.


var buffer = new ArrayBuffer(8);
buffer.byteLength; // 8


Specification Status Comment
Typed Array Specification Obsolete Superseded by ECMAScript 2015.
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'ArrayBuffer.prototype.byteLength' in that specification.
Standard Initial definition in an ECMA standard.
ECMAScript Latest Draft (ECMA-262)
The definition of 'ArrayBuffer.prototype.byteLength' in that specification.

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 7.0 (Yes) 4.0 (2) 10 11.6 5.1
Feature Android Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 4.0 (Yes) (Yes) 4.0 (2) 10 11.6 4.2

See also

Document Tags and Contributors

 Contributors to this page: jameshkramer, kdex, fscholz
 Last updated by: jameshkramer,