Array.prototype.reduceRight() - JavaScript | MDN

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Array.prototype.reduce()

The reduceRight() method of Array instances applies a function against an accumulator and each value of the array (from right-to-left) to reduce it to a single value.

How reduceRight() works without an initial value

The call to the reduceRight callbackFn would look something like this:

Indexed collections

Array.prototype.map()

Array.prototype.flat()

Array.prototype.flatMap()

TypedArray.prototype.reduceRight()

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This page was last modified on Jul 20, 2025 by MDN contributors.

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