Google Calendar Birthday Notifications for Android Contacts

Android has a nice feature of synchronizing birthdays that you have included in the contacts. It creates a new calendar named Birthdays which includes all the birthdays from the contacts as well as from the Google+ circle if you want. But my problem is that it does not allow you to add notifications for those dates.

I was thinking whether you could write a script to access the calendar and make some changes and voilà, I found out that google has a nice feature called Appscripts that allows you to write scripts that run on the google cloud. So I wrote a small script that adds this feature.


All you need to do to get started is go to and create a new blank project. Then you would need to give appropriate permissions to the project so it can access your data. To do that click Resources -> Advanced Google Services and then enable Calendar API. You would also need to enable access in *Google Developers Console too.

Calendar API

The overall logic is to create a new calendar and clone the events from the Birthdays calendar into it. Also you need to add notifications and make it a recurring event.

function addBdayNotifications() {
    var bdayCal, bdayNotifyCal;

    var calendars = CalendarApp.getAllCalendars();

    for (var i = 0; i < calendars.length; i++) {
        if (calendars[i].getName() == "Birthday Notifications") bdayNotifyCal = calendars[i];
        if (calendars[i].getName() == "Birthdays") bdayCal = calendars[i];

    if (bdayCal == undefined) return;

    if (bdayNotifyCal == undefined) {
        bdayNotifyCal = CalendarApp.createCalendar("Birthday Notifications");

    var currentYear = new Date().getFullYear();

    var fromDate = new Date(currentYear, 0, 1);
    var toDate = new Date(currentYear, 11, 31);

    var bdayEvents = bdayCal.getEvents(fromDate, toDate);
    var notifyEvents = bdayNotifyCal.getEvents(fromDate, toDate);

    // Maintain a list of event titles
    var notifyEventsTitle = [];
    for (i = 0; i < notifyEvents.length; i++) {
        if (i % 25 == 0) Utilities.sleep(1000);

    var items = 0;
    bdayEvents.forEach(function(evt) {
        var status = createEvent(bdayNotifyCal, notifyEventsTitle,
            evt.getTitle(), evt.getStartTime());

        if (status) items++;
        if (items % 5 == 0) Utilities.sleep(1000);

    Logger.log("%s events added to the calendar", items);

function createEvent(cal, eventList, title, time) {
    for (var i = eventList.length - 1; i >= 0; i--) {
        if (eventList[i] == title) return false;

    cal.createAllDayEventSeries(title, time,
        CalendarApp.newRecurrence().addYearlyRule(), {})
        .addPopupReminder(2 * 60);

    return true;

function createTrigger() {

The above code is pretty straightforward. Initially you look for the necessary calendars from your list of owned calendars. You then create a new calendar for notifications if one doesn’t exist already. After that create a list of birthdays present in the current year from both the calendars. Then its all about looping over the event list and creating a new one if one doesn’t exist.

During the event creation, you add an yearly recursion rule and set a pop-up reminder.

You would probably not want to trigger the code to run every time you add a contact. So we will make use of Triggers feature. It would have been nice if a trigger could be set on new event creation, but I could not find anything like that, therefore I added a daily trigger.

You could run in to a problem where google complains that you are creating too may events, in order to go around that I have added some delays but I haven’t arrived at an optimum solution for that.

Finally the last thing to do is to hide the calendar using .setHidden(true). This is nice feature that hides the calendar in the UI and solves the problem of having multiple birthdays on your calendar.


This is not a bullet proof solution for the problem. I would love to know if its possible to do this in different manner without using scripts.