JSFiddle - React, Tailwind, and code Playground

HTML

<div class='numbers'>1</div>
<div class='numbers'>1.0</div>
<div class='numbers'>1.00</div>

JavaScript

var elements = document.getElementsByClassName("numbers");
for (var i = 0, l = elements.length; i < l; i++) {
    elements[i].innerHTML = (+elements[i].innerHTML).toFixed(2);
}