Mark your countdown as public countdown and share it with the world. When you create a new countdown on webcountdown.net by default your countdown is NOT marked as public countdown.
If you want everybody to see the countdown for your event you can make your countdown available to the public in your countdown settings:
Just activate the option "List in public directory:"
Now your countdown will appear in the public directory shortly. Please be aware that the countdown may not appear immediately, because the directory is updated frequently.