Date of birth Calculator | Age Calculator

Date of birth Calculator | Age Calculator

// document.getElementById("age").innerHTML = d;

//}

var mdate = birthDate.toString();
var yearThen = parseInt(mdate.substring(0,4), 10);
var monthThen = parseInt(mdate.substring(5,7), 10);
var dayThen = parseInt(mdate.substring(8,10), 10);

var today = new Date();
var birthday = new Date(yearThen, monthThen-1, dayThen);
// alert(today.valueOf() + " " + birthday.valueOf());
var differenceInMilisecond = today.valueOf() - birthday.valueOf();
// alert(differenceInMilisecond);

var year_age = Math.floor(differenceInMilisecond / 31536000000);
var day_age = Math.floor((differenceInMilisecond % 31536000000) / 86400000);

if ((today.getMonth() == birthday.getMonth()) && (today.getDate() == birthday.getDate())) {
alert("Happy Birthday Dear !!! Enjoy Your Day");
//document.getElementById("age").innerHTML = ("Happy Birthday Dear");

}

var month_age = Math.floor(day_age/30);

day_age = day_age % 30;

var tMnt= (month_age + (year_age*12));
var tDays =(tMnt*30) + day_age;

if (isNaN(year_age) || isNaN(month_age) || isNaN(day_age)) {
document.getElementById("age").innerHTML = ("Invalid birthday - Please try again!");
}
else {
document.getElementById("age").innerHTML = year_age + " years " + month_age + " months " + day_age + " days"
+ "
or
"
+ tMnt + " months " + day_age + " days"
+ "
or
"
+ tDays + " days"
+ "
or
"
+ tDays*24 + " hours"
+ "
or
"
+ tDays*24*3600 + " seconds"
+ "
or
"
+ tDays*24*3600*1000 + " miliseconds" ;
}

}