Add or Migrate Events from Microsoft Outlook Calendar to Google Calender

If you’d like to migrate your events from another calendar service, click the name of the calendar you’ve been using. Below are instructions on how to import these events to Google Calendar from a few other calendar services.

Microsoft Outlook Calendar

• Open Outlook and go to File > Import and Export > Export to a file.
• Select Comma Separated Values (Windows).
• Select the calendar you want to export, save it to your desired location, then click Finished. (When exporting more than one year’s worth of data, we recommend that you divide your calendar into multiple, one-year segments and export each file separately; otherwise, you may encounter errors.)
• Select the desired date range of events to export, then click OK.
• In Google Calendar, ensure that you’ve created the calendar that you’d like to migrate events to. Then, at the bottom of the calendar list on the left, click the Add down-arrow button and selectImport Calendar.
• Click Browse and select the appropriate file, then select Open.
• From the drop-down menu, select the calendar to which you’d like to import events, then clickImport to complete the import. [source]