Date Diff with moment.js
by Laurie
HTML
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.10.2/moment.min.js"></script>
<div id="today"></div>
JavaScript
var a = moment([2015, 1, 1]);
$("#today").append(a.diff(moment(), 'days'));
$("#today").append('<br>');
var b = moment([2015, 1, 1]);
$("#today").append(moment().diff(b, 'days'));