How To Create A Countdown Timer Using JavaScript - GeeksforGeeks
Simple Date Time Countdown Timer Using JavaScript (May 2020)
How to Create a Countdown Clock with days, Hours, Minutes, and Seconds - CoderMen - Web Development and IT Solutions
GitHub - krishnadevz/timer: StopWatch/Countdown timer created in javascript css and in html use of this app is for setting timer in StopWatch In the browser
Build a Countdown Digital Alarm Clock Timer in Browser Using HTML5 CSS3 and Javascript - Coding Deekshi