2 calendars, 2 accounts, kept in step both ways. You choose whether colleagues see “Busy” or the real event.
Google · Outlook · iCloud · Fastmail · Nextcloud · any CalDAV · subscribed feed URLs (view only)
Free forever · No credit card
Each one is a named arrangement you can build on the free plan. It tells you which calendars to pick and which way events travel.
Your work calendar shows when you're unavailable, and nothing else about your personal life.
Book something on your phone and it is on your laptop, with its real title and location — and the other way round.
Your work meetings and everything else in both places, each with its real title and location.
Everything on the shared family calendar shows up on the calendar you actually check, in full.
Nothing here expires or degrades. These are the things the free plan does not do at all, so you can decide now instead of finding out later.
That is a third calendar, and free covers two. Everything you have set up carries over.
Free applies one rule to every calendar in a sync. Setting them apart per calendar is Pro.
Free syncs 30 days ahead. Anything beyond that is not copied until it comes into range.
Copies made on free carry a small SYNCDATE label. Paid plans drop it.
The free plan is built for one work calendar and one personal calendar. Once there is a second company in your week you need more accounts. On Pro you also get a different rule for each calendar inside one sync, so a client sees “Busy” while your own calendar keeps the real event.
No credit card, ever.