Everyone with the link watches the same countdown, and it ends at the same moment on every device, in each person's own language and time zone.

Yes. A countdown to a set time ends at the same instant everywhere and shows each viewer their local time. Choose Each viewer's local time to have everyone count to midnight where they are, as on New Year's Eve.

No. Anyone with the link can watch in any browser, and creating a countdown needs no sign-up.

Guests see a waiting screen until you start it, then every clock begins at once. A held date countdown also starts on its own when the date arrives.

Yes. Open Share, choose Embed, and paste the code into your page.

Yes. Ads keep it free, and they never appear during the final minute or at zero.