gistfile1.js

// to generate the number of days since a date

var days = (new Date() - new Date(2014, 7, 11)) / (1000 * 60 * 60 * 24);
var days_whole = Math.floor(days);

// in order to determine what the date is X days from now (we'll use days_whole)

var now = new Date();
var millis_to_date = days_whole * (1000 * 60 * 60 * 24);
var next_date = new Date(now.getTime() + millis_to_date);