Array: length - JavaScript | MDN

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The value of the length property is a nonnegative integer with a value less than 232.

Create empty array of fixed length

Setting length to a value greater than the current length creates a sparse array.

Array with non-writable length

The length property is automatically updated by the array when elements are added beyond the current length. If the length property is made non-writable, the array will not be able to update it. This causes an error in s

TypedArray.prototype.length

RangeError: invalid array length

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This page was last modified on May 2, 2026 by MDN contributors.

[Symbol.iterator]()

[Symbol.unscopables]

[Symbol.hasInstance]()

__defineGetter__()

__defineSetter__()

__lookupGetter__()

__lookupSetter__()

propertyIsEnumerable()

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