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Get the last item in an array using JavaScript

Get the last item in an array using JavaScript

Matthew C.

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The Problem

You want to get the last item in an array, how do you do this?

The Solution

There are multiple methods that can be used to get the last item in an array. Here are some ways to do this.

Using the Array length Property

You can use the length of an array and subtract 1 from it to get the index of the last item in an array:

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const arr = ["Ferrari", "Toyota", "Kia"];
const lastItem = arr[arr.length - 1];
console.log(lastItem); // Kia

You can also use the at() method, which returns an item at a given index:

Click to Copy
const arr = ["Ferrari", "Toyota", "Kia"];
const lastItem = arr.at(arr.length - 1);
console.log(lastItem); // Kia

These methods don’t change the array. If the array is empty, then lastItem will be undefined.

Using pop()

You can also use the pop() method to get the last item in an array:

Click to Copy
const arr = ["Ferrari", "Toyota", "Kia"];
const lastItem = arr.pop();
console.log(lastItem); // Kia
console.log(arr); // ["Ferrari", "Toyota']

This method removes the last item in the array and returns it. It modifies the array. Like the previous methods, if the array is empty, lastItem will be undefined.

Other Methods

You can use various other methods such as slice(), reduce(), or a for loop to get the last item in an array. These methods can be less readable than the methods described above. The methods that modify the array or create a new item will be less efficient, in terms of the number of operations that can be performed per second, than solutions that only read what the last item is. However, the performance difference is unlikely to be significant in most applications.

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