Iterator.prototype.forEach()

Baseline Newly available

This feature works across the latest devices and browser versions. This feature might not work in older devices or browser versions. It's been available across browsers since March 2025.

The forEach() method of Iterator instances is similar to Array.prototype.forEach(): it executes a provided function once for each element produced by the iterator.

Syntax

forEach(callbackFn)

Parameters

callbackFn

A function to execute for each element produced by the iterator. Its return value is discarded. The function is called with the following arguments:

element: The current element being processed.
index: The index of the current element being processed.

Return value

undefined.

Description

forEach() iterates the iterator and invokes the callbackFn function once for each element. Unlike most other iterator helper methods, it does not work with infinite iterators, because it is not lazy.

Examples

Using forEach()

new Set([1, 2, 3]).values().forEach((v) => console.log(v));

// Logs:
// 1
// 2
// 3

This is equivalent to:

for (const v of new Set([1, 2, 3]).values()) {
  console.log(v);
}

Specifications

Specification
ECMAScript® 2027 Language Specification # sec-iterator.prototype.foreach

Browser compatibility

	Desktop					Mobile							Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS	Bun	Deno	Node.js
`forEach`	122 117–119	122 117–119	131	108 103–105	18.4	122 117–119	131	81 78–79	18.4	26.0 24.0–25.0	122 117–119	18.4	1.1.31	1.39	22.0.0