How to Make an ICS File

Apple’s iCalendar application lets you create and share appointments with other iCalendar users, who export and import this information with ICS formatted files. The ICS format has found acceptance with other calendar applications, such as Google’s Web-based calendar and the popular Microsoft Outlook application. This widespread acceptance has made it possible for one person to invite another person to an event simply by sending an ICS file.

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An ICS file transfers calendar data from one type of calendar to another.

Outlook

Step

Open the appointment that you wish to place in the ICS file.

Step

Open the "Save as" menu. Click “File” from the toolbar at the top of the screen, and then click “Save as.”

Step

Enter a file name, and select “iCalendar Format” from the “Save as type” menu bar.

iCalendar

Step

Select the iCalendar event that you wish to place in the ICS file.

Step

Drag the event from the calendar and place it on your desktop. Dragging an iCalendar event to the desktop automatically creates an ICS file.

Step

Attach the ICS file to an email, and send it to event invitees.

Google Calendar

Step

Open the calendar settings. Select the white down arrow in the small blue box next to the name of the calendar in the far left column. Click on the “Calendar settings” submenu.

Step

Select the green "ICAL" icon.

Step

Copy the link. This link allows access to a new ICS file that contains your calendar’s events.