Answer by hiren gamit for How do I get the difference between two Dates in JavaScript?

function checkdate() {    var indate = new Date()    indate.setDate(dat)    indate.setMonth(mon - 1)    indate.setFullYear(year)    var one_day = 1000 * 60 * 60 * 24    var diff = Math.ceil((indate.getTime() - now.getTime()) / (one_day))    var str = diff +" days are remaining.."    document.getElementById('print').innerHTML = str.fontcolor('blue')}