jquery calculating age based on dob

Question

I have a textfield where the user enters the date of birth in mm/dd/yyyy format. I want to autofill the age field for the user based on their entered dob.

the age textfield should be populated when user tabs out of the dob field.

what is the jQuery way of doing this?

score 3 · Accepted Answer · edited May 23 '17 at 11:53

3

See Calculate age in JavaScript for a function to calculate the age that handles leap years appropriately.

You can then use that function to calculate the user's age, like so:

var age = getAge(new Date($("#date").value()));

.. and then set the age field to that number:

$("#date").bind("blur", function() { $("#age").value(age) });

edited May 23 '17 at 11:53

Community

1
1

answered May 08 '11 at 01:29

Fixed (with a bit of laziness ;) – May 08 '11 at 01:36

score 0 · Answer 2 · edited Jan 03 '17 at 01:40

I came up with a simple solution for this. It's an jQuery change function that sends the value to an input age field.

$(document).ready(function() {

    $('#dob input').change(function() {

        var today = new Date();
        var dd = Number(today.getDate());
        var mm = Number(today.getMonth() + 1);

        var yyyy = Number(today.getFullYear());

        var myBD = $('#dob input').val();
        var myBDM = Number(myBD.split("/")[0])
        var myBDD = Number(myBD.split("/")[1])
        var myBDY = Number(myBD.split("/")[2])
        var age = yyyy - myBDY;

        if (mm < myBDM) {
            age = age - 1;
        } else if (mm == myBDM && dd < myBDD) {
            age = age - 1;
        }

        $('#age input').val(age);
    });

});

score 0 · Answer 3 · edited Jan 03 '17 at 01:39

Here we test it by taking start and end date. You can also use it to calculate age in months and days.

var end = new Date(2015, 09, 02, 00, 0, 0, 0),
    begin = new Date(2015, 09, 1, 00, 0, 0, 0),
    e = new Date(end),
    b = new Date(begin),
    bMonth = b.getMonth(),
    bYear = b.getFullYear(),
    eYear = e.getFullYear(),
    eMonth = e.getMonth(),
    bDay = b.getDate(),
    eDay = e.getDate() + 1;

if ((eMonth == 0) || (eMonth == 2) || (eMonth == 4) || (eMonth == 6) ||
    (eMonth == 7) || (eMonth == 9) || (eMonth == 11)) {
    var eDays = 31;
}

if ((eMonth == 3) || (eMonth == 5) || (eMonth == 8) || (eMonth == 10)) {
    var eDays = 30;
}

if (eMonth == 1 && ((eYear % 4 == 0) && (eYear % 100 != 0)) ||
    (eYear % 400 == 0)) {
    var eDays = 29;
}

if (eMonth == 1 && ((eYear % 4 != 0) || (eYear % 100 == 0))) {
    var eDays = 28;
}

if ((bMonth == 0) || (bMonth == 2) || (bMonth == 4) || (bMonth == 6) ||
    (bMonth == 7) || (bMonth == 9) || (bMonth == 11)) {
    var bDays = 31;
}

if ((bMonth == 3) || (bMonth == 5) || (bMonth == 8) || (bMonth == 10)) {
    var bDays = 30;
}

if (bMonth == 1 && ((bYear % 4 == 0) &&
        (bYear % 100 != 0)) || (bYear % 400 == 0)) {
    var bDays = 29;
}

if (bMonth == 1 && ((bYear % 4 != 0) || (bYear % 100 == 0))) {
    var bDays = 28;
}

var FirstMonthDiff = bDays - bDay + 1;

if (eDay - bDay < 0) {
    eMonth = eMonth - 1;
    eDay = eDay + eDays;
}

var daysDiff = eDay - bDay;

if (eMonth - bMonth < 0) {
    eYear = eYear - 1;
    eMonth = eMonth + 12;
}

var monthDiff = eMonth - bMonth,
    yearDiff = eYear - bYear;

if (daysDiff == eDays) {
    daysDiff = 0;
    monthDiff = monthDiff + 1;

    if (monthDiff == 12) {
        monthDiff = 0;
        yearDiff = yearDiff + 1;
    }
}

if ((FirstMonthDiff != bDays) && (eDay - 1 == eDays)) {
    daysDiff = FirstMonthDiff;
}
console.log(yearDiff + " Year(s)" + " " +
    monthDiff + " month(s) " + daysDiff + " days(s)");

score 0 · Answer 4 · edited Dec 28 '16 at 13:28

0

function (row) 
{
    var age = 0;
    var birthday = row["FechaNacimiento"];

    age = new Date().getFullYear() - birthday.getFullYear();

    if (new Date() < birthday.setFullYear(birthday.getFullYear() + age)) 
    {
        age--;
    }

    return age;
}

late but this works...

edited Dec 28 '16 at 13:28

Daniel Corzo

1,055
2
19
32

answered Dec 28 '16 at 13:17

Francisco Moreno

1
1

score 0 · Answer 5 · edited Jan 03 '17 at 01:44

On blur of your textbox, you'll have to calculate the date difference between what they entered and now().

$('#birthdate').blur(function() {
    $("#ageTextBox").val(getAge(parseDate($('#birthdate').val())));
});

function getAge(birthDate) {
    var now = new Date();

    function isLeap(year) {
        return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
    }

    // days since the birthdate    
    var days = Math.floor((now.getTime() - birthDate.getTime()) / 1000 / 60 / 60 / 24);
    var age = 0;
    // iterate the years
    for (var y = birthDate.getFullYear(); y <= now.getFullYear(); y++) {
        var daysInYear = isLeap(y) ? 366 : 365;
        if (days >= daysInYear) {
            days -= daysInYear;
            age++;
            // increment the age only if there are available enough days for the year.
        }
    }
    return age;
}

score 0 · Answer 6 · edited Jan 03 '17 at 01:32

0

Try the jquery.dates plugin

var d = $("#mytextboxID").dateDiff("unit", date);

edited Jan 03 '17 at 01:32

Emile Bergeron

17,074
5
83
129

answered May 08 '11 at 01:38

robert

1,523
5
19
27

This plugin looks to be dead. The website is now offline. – Emile Bergeron Jan 03 '17 at 01:33

jquery calculating age based on dob

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