Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.
BusyCal - powerful calendar app for macOS
Qbix Calendar - Put a calendar on your menu bar, and access your calendar, weather, and more at a glance.
Google Calendar - Spend less time managing your day & more time enjoying it
Dato - Better menu bar clock with calendar and time zones
Superpowered - Power through the day without your calendar