JavaScript - get unique values in array

In this article, we would like to show you how to get unique values in a JavaScript array.

The below example presents the use of Set object that lets us store unique values of any type.

The constructor of Set takes an iterable object and the spread operator (...) transforms the Set object back into the array.

Runnable example:

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let array = ['A', 'B', 'B', 'B', 'C', 'C'];

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let unique = [...new Set(array)];

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console.log(unique); // ['A', 'B', 'C']

Second example: 

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let array = [1, 1, 'B', 'B', 'C', 'C'];

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let unique = [...new Set(array)];

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console.log(unique); // [1, 'B', 'C']

Note:

Sets are a new object type introduced in ES6 (ES2015).

• Set - MDN Web Docs