JSFiddle - React, Tailwind, and code Playground

by Techsolo

HTML

<input id="input" value="5487445.46878" />
<button>Transform</button>

JavaScript

$(document).ready(function () {
    $('button').click(function (e) {
        var input = $('#input').val();
        var parts = input.split('.');
        var part1 = parts[0].replace(/(\d)(?=(\d\d\d)+(?!\d))/g, "$1,");
        var part2 = parts[1];
        
        alert(part1 + '.' + part2);
    });
});