How to Remove Duplicates in an Array in JavaScript

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How to Remove Duplicates in an Array in JavaScript ?

Answer

To remove duplicates from an array in JavaScript, you can use various methods such as using a Set or filter function.

✐ Examples

1 Remove Duplicates using Set

In this example,

We create an array named `numbers` with duplicate elements.
We convert the array to a Set to automatically remove duplicates.
Finally, we convert the Set back to an array to get the array without duplicates.

JavaScript Program

let numbers = [1, 2, 2, 3, 4, 4, 5];
let uniqueNumbers = [...new Set(numbers)];
console.log('Array without duplicates:', uniqueNumbers);

Output

Array without duplicates: [ 1, 2, 3, 4, 5 ]

2 Remove Duplicates using Filter

In this example,

We create an array named `colors` with duplicate strings.
We use the `filter` method to create a new array with only unique elements.
Finally, we get an array without duplicates using the filter method.

JavaScript Program

let colors = ['red', 'green', 'blue', 'green', 'yellow', 'blue'];
let uniqueColors = colors.filter((value, index, self) => self.indexOf(value) === index);
console.log('Array without duplicates:', uniqueColors);

Output

Array without duplicates: [ 'red', 'green', 'blue', 'yellow' ]

Summary

In this tutorial, we learned How to Remove Duplicates in an Array in JavaScript language with well detailed examples.

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How to Remove Duplicates in an Array in JavaScript

How to Remove Duplicates in an Array in JavaScript ?

Answer

✐ Examples

1 Remove Duplicates using Set

JavaScript Program

Output

2 Remove Duplicates using Filter

JavaScript Program

Output

Summary

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