Widely available Supported across all major browsers. Safe to use in production.

Array fill()

The fill() method of Array instances changes all elements within a range of indices in an array to a static value. It returns the modified array.

Arrays

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
javascript.builtins.Array.fill
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Built-in object
TypedArray.fill

The fill() method of TypedArray instances changes all elements within a range of indices in a typed array to a static value. It returns the modified typed array. This method has the same algorithm as Array.prototype.fill().
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1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
// Initializing an array
new Array(5).fill(0); // [0, 0, 0, 0, 0]

// Partially filling an array
[1, 2, 3, 4, 5].fill(9, 2, 4); // [1, 2, 9, 9, 5]

Live demo

Array. initialize

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range specifiedfill

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de-ta. initialize(reset)

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Use cases

  • Using Array fill()

    The fill() method of Array instances changes all elements within a range of indices in an array to a static value.

Cautions

  • No specific concerns. Stable across all major browsers.

Accessibility

  • When updating the DOM dynamically, announce important changes to assistive technology with aria-live regions.

Related links