Remove Duplicate Values from JavaScript Array

The Set object, which allows you to store unique values of any type, can be used to eliminate duplicate values from a JavaScript array. Put differently, Set will eliminate duplicates for us automatically.

Here’s an example:

// Your array with duplicates
let arrayWithDupes = [1, 2, 3, 4, 2, 3, 5, 6, 1];

// Creating a Set from the array to get unique values
let uniqueSet = new Set(arrayWithDupes);

// Converting the Set back to an array
let uniqueArray = Array.from(uniqueSet);

// Ta-da! Now uniqueArray has only unique values
console.log(uniqueArray);

Alternatively, you can use the filter() method to remove duplicates. 

const names = ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Nancy", "Carl"];
let unique = names.filter((value, index, self) => {
  return self.indexOf(value) === index;
});
console.log(unique); // ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Carl"]

Please be aware that large arrays are not a good fit for the filter() method. using the Set object is a better option.

Happy Coding! ❤️