How to Create a Set from an Array in JavaScript

To create a Set from an array in JavaScript, pass the array to the Set() constructor. For example:

const arr = [1, 2, 3];
const set = new Set(arr);

console.log(set); // Set(3) { 1, 2, 3 }

console.log(set.has(2)); // true

set.delete(2);

console.log(set); // Set(2) { 1, 3 }

A Set object only stores unique values, so it won’t contain any duplicates.

const arr = [1, 1, 2, 3, 3, 4];
const set = new Set(arr);

// Set(4) { 1, 2, 3, 4 }
console.log(set);

This makes it useful for removing duplicate elements from an array without mutating it, for example:

const arr = [1, 1, 2, 3, 3, 4];

const distinct = Array.from(new Set(arr));

// [1, 2, 3, 4]
console.log(distinct);

11 Amazing New JavaScript Features in ES13

This guide will bring you up to speed with all the latest features added in ECMAScript 13. These powerful new features will modernize your JavaScript with shorter and more expressive code.