see how many unique values in array javascript code example
Example 1: javascript find unique values in array
// usage example:
var myArray = ['a', 1, 'a', 2, '1'];
var unique = myArray.filter((v, i, a) => a.indexOf(v) === i);
// unique is ['a', 1, 2, '1']
Example 2: unique values in array javascript
let uniqueItems = [...new Set(items)]