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---
title: Float16Array
slug: Web/JavaScript/Reference/Global_Objects/Float16Array
page-type: javascript-class
browser-compat: javascript.builtins.Float16Array
sidebar: jsref
---

The **`Float16Array`** typed array represents an array of 16-bit floating point numbers in the platform byte order. If control over byte order is needed, use {{jsxref("DataView")}} instead. The contents are initialized to `0` unless initialization data is explicitly provided. Once established, you can reference elements in the array using the object's methods, or using standard array index syntax (that is, using bracket notation).

`Float16Array` is a subclass of the hidden {{jsxref("TypedArray")}} class.

> [!NOTE]
> Float16 support is not universal, both in the JavaScript API and the underlying CPU architecture. Using it may result in slower performance on some platforms. It is intended for interacting with highly optimized and performance-sensitive systems such as [float-backed canvases](https://github.com/w3c/ColorWeb-CG/blob/main/canvas_float.md), WebGPU, WebGL, and deep learning models including [stable diffusion](https://github.com/huggingface/blog/blob/main/stable_diffusion.md).

## Constructor

- {{jsxref("Float16Array/Float16Array", "Float16Array()")}}
  - : Creates a new `Float16Array` object.

## Static properties

_Also inherits static properties from its parent {{jsxref("TypedArray")}}_.

- {{jsxref("TypedArray/BYTES_PER_ELEMENT", "Float16Array.BYTES_PER_ELEMENT")}}
  - : Returns a number value of the element size. `2` in the case of `Float16Array`.

## Static methods

_Inherits static methods from its parent {{jsxref("TypedArray")}}_.

## Instance properties

_Also inherits instance properties from its parent {{jsxref("TypedArray")}}_.

These properties are defined on `Float16Array.prototype` and shared by all `Float16Array` instances.

- {{jsxref("TypedArray/BYTES_PER_ELEMENT", "Float16Array.prototype.BYTES_PER_ELEMENT")}}
  - : Returns a number value of the element size. `2` in the case of a `Float16Array`.
- {{jsxref("Object/constructor", "Float16Array.prototype.constructor")}}
  - : The constructor function that created the instance object. For `Float16Array` instances, the initial value is the {{jsxref("Float16Array/Float16Array", "Float16Array")}} constructor.

## Instance methods

_Inherits instance methods from its parent {{jsxref("TypedArray")}}_.

## Examples

### Different ways to create a Float16Array

```js
// From a length
const float16 = new Float16Array(2);
float16[0] = 42;
console.log(float16[0]); // 42
console.log(float16.length); // 2
console.log(float16.BYTES_PER_ELEMENT); // 2

// From an array
const x = new Float16Array([21, 31]);
console.log(x[1]); // 31

// From another TypedArray
const y = new Float16Array(x);
console.log(y[0]); // 21

// From an ArrayBuffer
const buffer = new ArrayBuffer(32);
const z = new Float16Array(buffer, 4, 4);
console.log(z.byteOffset); // 4

// From an iterable
const iterable = (function* () {
  yield* [1, 2, 3];
})();
const float16FromIterable = new Float16Array(iterable);
console.log(float16FromIterable);
// Float16Array [1, 2, 3]
```

## Specifications

{{Specifications}}

## Browser compatibility

{{Compat}}

## See also

- [JavaScript typed arrays](/en-US/docs/Web/JavaScript/Guide/Typed_arrays) guide
- {{jsxref("TypedArray")}}
- {{jsxref("ArrayBuffer")}}
- {{jsxref("DataView")}}