Lightning Calendar - Organize your life — it’s about time!
Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.
Simple Calendar - A simple calendar with events (optional recurring and reminders), week numbers and a customizable...
Google Calendar - Spend less time managing your day & more time enjoying it
Calendar Lock PEA - Calendar Lock PEA is an encrypted desktop calendar with a day, week and month view. The shown calendars are never stored unencrypted on your disk, but exist only in the RAM. Platform-independent, Open Source, no installation or registration required.
Itsycal - Itsycal for Mac. Itsycal is a tiny menu bar calendar. If you want, it will display your events as a companion to the Mac Calendar app. You can also create and delete (but not edit) events. Download Itsycal for macOS 10.