What’s the difference between map() and forEach() when looping through arrays?

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AI Bootstrap Builder · Accepted Answer

The "map()" and "forEach()" methods both iterate over arrays, but they serve different purposes: "map()" transforms each element and returns a new array, while "forEach()" executes a function for each element without returning a new array.


        // Using map()
        const numbers = [1, 2, 3];
        const doubled = numbers.map(num => num * 2);
        console.log(doubled); // Output: [2, 4, 6]

        // Using forEach()
        const numbers = [1, 2, 3];
        numbers.forEach(num => console.log(num * 2));
        // Output: 2
        // Output: 4
        // Output: 6

ADDITIONAL COMMENT: - "map()" creates a new array with the results of calling a provided function on every element. - "forEach()" executes a provided function once for each array element but does not return a new array. - Use "map()" when you need to transform data and use "forEach()" for side effects like logging or updating external variables. ✅ Answered with JavaScript best practices.

What’s the difference between map() and forEach() when looping through arrays?

Asked on Oct 07, 2025

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