The fill() method fills all the elements of a typed array from a start index to an end index with a static value. This method has the same algorithm as Array.prototype.fill(). TypedArray is one of the typed array types here.


typedarray.fill(value[, start = 0[, end = this.length]])


Value to fill the typed array with.
start Optional
Start index. Defaults to 0.
end Optional
End index (not included). Defaults to this.length.

Return value

The modified array.


The elements interval to fill is [start, end).

The fill() method takes up to three arguments value, startstart and end. The start and end arguments are optional with default values of 0 and the length of the this object.

If start is negative, it is treated as length+start where length is the length of the array. If end is negative, it is treated as length+end.


Using fill()

new Uint8Array([1, 2, 3]).fill(4);         // Uint8Array [4, 4, 4]
new Uint8Array([1, 2, 3]).fill(4, 1);      // Uint8Array [1, 4, 4]
new Uint8Array([1, 2, 3]).fill(4, 1, 2);   // Uint8Array [1, 4, 3]
new Uint8Array([1, 2, 3]).fill(4, 1, 1);   // Uint8Array [1, 2, 3]
new Uint8Array([1, 2, 3]).fill(4, -3, -2); // Uint8Array [4, 2, 3]


Since there is no global object with the name TypedArray, polyfilling must be done on an "as needed" basis. Use the following "polyfill" along with the Array.prototype.fill() polyfill.

// https://tc39.github.io/ecma262/#sec-%typedarray%.prototype.fill
if (!Uint8Array.prototype.fill) {
  Uint8Array.prototype.fill = Array.prototype.fill;


ECMAScript (ECMA-262)
The definition of 'TypedArray.prototype.fill' in that specification.

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
fillChrome Full support 45Edge Full support 14Firefox Full support 37IE No support NoOpera Full support 36Safari Full support 9.1WebView Android No support NoChrome Android Full support 45Firefox Android Full support 37Opera Android No support NoSafari iOS Full support 9.3Samsung Internet Android Full support 5.0nodejs Full support 4.0.0


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See also