Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.
Google Calendar - Spend less time managing your day & more time enjoying it
Menu Bar Calendar - Quickly access a monthly calendar from your menu bar.
Superpowered - Power through the day without your calendar
Grila - Calendar for keyboard addicts instantly available on a hotkey.
BusyCal - powerful calendar app for macOS