Merge ICS files into one calendar
Combine several .ics files — exports, invitations, replies — into one calendar file, with copies of the same event matched instead of doubled.
About this conversion
Merging calendars by pasting files together leaves every meeting that appears in two of them twice — and an invitation, its update and the guest's reply are three copies of one event. Here events are matched by their identity, not their text: the newest version wins, the guests from all copies are kept with their latest answers, and a cancelled occurrence of a series becomes a skipped date in that series.
Just want to look inside it?
The same tool without converting anything: open the file and read it.
The same calendar, any way out
The file is read once and stays open, so the format is picked at the end: the same events can leave here as XLSX, CSV, CSV for Google Calendar or PDF. The same meeting found in an invitation, a reply and an export is recognised as one event, and its time is the same moment whichever way it was written — with a time zone, in UTC or as a whole day.
Questions
- What about invitations that came by email?
- Drop the .eml messages too: the calendar inside each invitation is read and matched with the rest.