How the countdown works
The calculator builds a precise timestamp from your target date — plus a time of day if you set one — and compares it against your device's clock once per second. The days, hours, minutes and seconds boxes always sum to the exact remaining time, so the days figure is the number of full 24-hour blocks left, not calendar days.
The breakdown below the timer works in calendar days instead: it counts each date from tomorrow through the target, which is how most people think about "days until." That is also how the working-days figure is produced — the calculator walks every date in the range and counts only Monday to Friday, so the answer is exact regardless of which weekday the countdown starts on. Public holidays are not excluded, since they vary by country.
Timezones
Everything runs in your device's local timezone. If you are counting down to a global event announced for another timezone — a product launch, a game release, a livestream — convert the announced time to your local time first, or simply leave the time blank to count down to midnight of that date where you are.
Counting down to launches and releases
Rumored or expected dates for product launches are exactly that — expected. The quick-pick chips for upcoming launch events use the most widely reported dates and disappear automatically once they pass, but a date is only certain once the company officially announces it. For your own deadlines, exams, weddings and trips, the countdown is exact to the second.
Sharing and saving countdowns
The copy-link button encodes your date, time and event name into the page address. Anyone opening that link sees the same countdown ticking live in their own timezone — nothing is stored on a server.
The save button keeps a countdown in your browser's local storage on this device, so your named events — birthdays, exams, trips, launches — are waiting under "My countdowns" whenever you come back. Saved countdowns never leave your device and are removed if you clear your browsing data, so use the copy-link button as a backup for anything important.