World Time Buddy - Effortless time conversion and world time.
Fantastical 2 - Fantastical, the Mac calendar app you'll enjoy using. Quickly create new events with natural language input and more.
Time.is - exact time in any location
Google Calendar - Spend less time managing your day & more time enjoying it
timeanddate.com - Free Clock for your website or blog!
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.