JavaScript Sum Array Values

In JavaScript, you can easily sum all the values of an array using a variety of methods. In this guide, we'll explore some of the most common methods for summing array values in JavaScript.

Example Array

For the purposes of this guide, we'll use the following array as an example:

const numbers = [1, 2, 3, 4, 5];

Method 1: For Loop

One of the most basic ways to sum all the values in an array is to use a for loop. Here's an example:

let sum = 0;

for (let i = 0; i < numbers.length; i++) {
  sum += numbers[i];
}

console.log(sum); // Output: 15

In this method, we initialize a sum variable to 0 and then loop through the array, adding each value to the sum as we go.

Method 2: For Each

Another common way to sum array values is to use the forEach() method. Here's an example:

let sum = 0;

numbers.forEach((number) => {
  sum += number;
});

console.log(sum); // Output: 15

In this method, we initialize a sum variable to 0 and then call the forEach() method on the array. For each value in the array, we add it to the sum.

Method 3: Reduce

One of the most powerful ways to work with arrays in JavaScript is to use the reduce() method. Here's an example:

const sum = numbers.reduce((total, number) => {
  return total + number;
}, 0);

console.log(sum); // Output: 15

In this method, we call the reduce() method on the array and provide a function that takes two arguments: the total (which starts at 0) and the current array value. For each value in the array, we add it to the total and return the new total.

Conclusion

As you can see, there are several ways to sum all the values in an array in JavaScript. Whether you prefer a basic for loop, the forEach() method, or the powerful reduce() method, there's almost certainly a solution that suits your needs. So next time you need to sum an array in JavaScript, try one of these methods!