How to create a countdown clock?

I was looking at a countdown clock of an email of a renowned company and tracked back the source. I came across the website

Some of the good things I found:

  • Creating a title
  • Changing size and various parameters
  • Smooth animation
  • Embed or Share
  • Email Countdown

Feel free to check the site and let me know your experience in comments.

Happy Coding. Keep Sharing.