JSFiddle - React, Tailwind, and code Playground

by Aleksandra Strelkova

HTML

<input id="partitioned" type="text" maxlength="16" />

JavaScript

var str = document.getElementById('partitioned');
var arr = [];

for (var i = 0; i < str.length; i+=4) {
    arr.push(str.slice(i, i + 4));
}

alert(arr.join(" "));