Hourglass - Hourglass is the most advanced simple countdown timer for Windows.
TimeLeft - TimeLeft is a versatile desktop utility - it can be used as a countdown clock, reminder, clock...
wnr - Better than pomodoro, this timer app balances work and rest.
Dial - Quick & beautiful macOS timer.
Free Countdown Timer - Free Countdown Timer is a free, full-featured and user-friendly countdown timer for Windows
DS Clock - Keep your time synchronized with Atomic Time servers, using customizable digital desktop clock with westminster chimes.