NumberTally How the Live Countdown Works
Your target date and time are converted to an exact millisecond timestamp. Every second, the page subtracts “now” from that timestamp and splits the difference into days, hours, minutes, and seconds — the same breakdown you’d get from dividing by 86,400,000 ms/day, 3,600,000 ms/hour, and so on, keeping only whole units at each step. When the difference hits zero, the timer flips to a “time’s up” state instead of going negative.
Sharing and Saving Countdowns
The share link encodes the exact target moment in UTC (“?to=2027-01-01T05:00:00.000Z”), so anyone who opens it anywhere in the world sees the same countdown — no account needed. Saved countdowns live in your browser’s local storage, which means they’re private to your device and survive tab closes, but won’t follow you to another computer.
Frequently Asked Questions
How does the share link work?
The link carries your target date, time, and label as URL parameters. Anyone who opens it sees the same live countdown, with no account or sign-up.
Do I need an account to use the countdown timer?
No. The timer runs entirely in your browser, and saved countdowns are stored locally on your device.
What happens when the countdown reaches zero?
It switches to a “time’s up” message and stops at zero instead of counting into negative numbers.
Does the timer keep running if I close the tab?
The live ticking only runs while the page is open, but the target moment is fixed — reopen the page (or your share link) any time and the remaining time is recomputed instantly. Saved countdowns persist in this browser.
Which time zone does the countdown use?
Dates you type use your device’s local time zone. Share links are smarter: they carry the exact moment in UTC, so a countdown shared from New York counts down to the same instant for someone opening it in Chicago or London.