Recommended Calendars

A calendar is a map of your life: who you meet, when, where, the doctor visits, the deadlines, the people you see most. Big Tech calendars read all of it and feed it into the same profile that sells ads. A private calendar breaks that and it does so in one of two ways. Some encrypt your events so the provider cannot read them at all. Others keep the open CalDAV standard so they sync with everything and simply stop the profiling. Which one you want comes down to whether you need the provider shut out completely or you need a calendar that works everywhere.

How to choose a calendar

The two goals pull against each other. End-to-end encryption scrambles your events so the provider cannot read them but it usually means giving up CalDAV, the open standard that lets any app sync your calendar so the encrypted options work mainly through their own apps. CalDAV services sync with everything and drop the ad profiling but the server can still read your events unless you host it yourself. Pick by which you need more: the provider shut out or your calendar working everywhere.

Here are some things to look for.

End-to-end encryption. Events are encrypted on your device so the provider cannot read your schedule.
CalDAV support. Works with standard calendar apps and syncs across your devices. Encrypted services often drop this.
Open-source apps. So the privacy and encryption can be checked instead of taken on trust.
A self-hosting option. Run it on your own server and you are the only one who can read your events.
No ad profiling. Paid by a subscription or donations, not by mining your schedule.
Apps for the platforms you use. Windows, Mac, Linux, iOS, and Android or a standard client that covers them.