Shareable countdown link
Send one link and everyone’s screen hits zero at the same instant, in any time zone, even if their device clock is off.
Clock check
Checking your device clock against the server…
Alarm & notification settings
Sound needs one tap on the page first (a browser rule). Keep this tab open: closing it stops every timer’s alarm. Why timers stay accurate in background tabs.
Why a timestamp link beats “start a 10-minute timer”
If you tell a group to start a 10-minute timer, everyone starts it at a slightly different moment, and anyone who opens it late gets a full 10 minutes. A shareable countdown link instead stores the end moment itself, as milliseconds since 1 January 1970 UTC (the standard way computers record time). Each screen subtracts its current time from that fixed moment, so the person who opens the link with three minutes to go sees three minutes.
The weak point is the device clock. Phones and computers normally synchronise to internet time servers, but a clock set by hand can be minutes out. This page measures the difference against our server at load, NTP-style (halfway through the round trip), and shifts the countdown to match.
Good uses
- A live stream, webinar or product launch starting soon
- Classes or workshops coming back from a break, across several rooms or at home
- Online auctions, ticket drops and sales that open at a set minute
- A game night or a shared deadline between remote teammates
Questions
How does a shareable countdown link stay in sync?
The link contains the exact end moment as a universal timestamp, not a duration. Every device works out the time left from that fixed moment and its own clock, so everyone reaches zero together, whatever their time zone and whenever they opened the link.
What if someone’s device clock is wrong?
The page checks your device clock against our server when it loads and corrects for the difference, so a phone that is a minute fast still hits zero at the right moment. If that check fails (for example offline), it falls back to the device clock and says so.
Do time zones matter?
No. You pick the moment in your own time zone; the link stores it as UTC, and each visitor sees the end time in their local time.
Is this for a holiday or birthday countdown?
It works for any moment, but it is built for short, live events: a class starting, a stream going live, a sale opening, a break ending. For countdowns to holidays and life events weeks away, a days-until calendar is a better fit.