Countdown Calculator
How it works
The target date and time is compared against your device's clock, right now, and the gap between them is split into days, hours, minutes and seconds. That comparison reruns every second, which is what makes the display tick on its own without you touching the form again.
Frequently asked questions
What happens when the target time passes while the page is open?
The countdown keeps running — it just switches to counting up, labeled as time "ago" instead of time remaining. Nothing errors and nothing resets; the target you set stays exactly where you left it.
Whose time zone does the target use?
Your device's local time zone. Typing 6:00 PM means 6:00 PM where you are, and the countdown compares that against your device's own clock, so there is no zone to get wrong.
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