With the emerging use of electronic calendars services on the Internet the users are constantly increasing the number of Calendar(Event) platforms they use and the need to have them synchronized in one place is increasing. In this research we presented the evolution of the electronic services for calendars, and give overview of the APIs they use, along with protocols and interfaces to these services. We introduce an idea to create Event Aggregation model in order to exchange, modify and synchronize information about events from different calendar platforms. The solution is explained by protocols and patterns, as well as the structure and architecture, and platforms included We have implemented conceptual model using PHP/MySQL and WordPress open source as WordPress plugin which can get events from Eventbrite.com, Meetup.com, Facebook.com, iCalendar file, Google Calendar, Outlook Calendar and converted in standard iCalendar format which is stored in MySQL database and presented with GUI.