How do I make an array with unique elements (remove duplicates) - JavaScript?

Let’s say the following is our array with duplicate elements −

var duplicateNumbers = [10, 20, 100, 40, 20, 10, 100, 1000];

We want the output to be −

[10, 20, 100, 40, 1000];

To display only the unique elements, use the concept of filter.

Example

Following is the code −

var duplicateNumbers = [10, 20, 100, 40, 20, 10, 100, 1000];
console.log("With Duplicates Values=");
console.log(duplicateNumbers);
var noDuplicateNumbersArray = duplicateNumbers.filter(function (value, index, array) {
    return array.indexOf(value) === index;
}
);
console.log("Without Duplicates Values=")
console.log(noDuplicateNumbersArray);

To run the above program, you need to use the following command −

node fileName.js.

Here, my file name is demo234.js.

Output

The output is as follows −

PS C:\Users\Amit\JavaScript-code> node demo234.js
With Duplicates Values=
[
    10,   20, 100,
    40,   20,  10,
   100, 1000
]
Without Duplicates Values=
[ 10, 20, 100, 40, 1000 ]