Log in to your Facebook account and type “countdown clock” (without quotes) in the search field on the page. Click the “See more results for countdown clock” link that displays in the drop-down list, and then click the “Apps” link on the left side to bring up all the applications that perform this task.
Beside this, can I put a countdown clock on Facebook?
You can install a countdown clock on your Facebook page by installing the countdown clock app offered on the Facebook website. The app allows you to customize the color, time, date and type of event that you wish to display. The countdown clock can then be added to your wall, fan page or even a friend’s wall.