Time & Random
Countdown Timer
Count down to a date and time in your browser.
Results appear here.
What the result means
Choose a date and time and start the timer. The target is read as local time, because a datetime-local field does not carry a zone offset. Remaining time is the target minus Date.now(), split into days, hours, minutes, and seconds. The page ticks about once a second. When the remaining time reaches zero, or when the target is already in the past, the result says Done and does not show a negative count. Starting again clears the previous timer so two countdowns do not run together. Nothing is stored, and no server is asked for the time. A hidden browser tab may slow or pause the tick, so the numbers can jump when you come back. The next tick catches up from the clock rather than from the number of intervals that fired.
Related tools
Questions
Which timezone is the target?
The target is interpreted in the browser's local zone. A datetime-local value has no offset of its own. If you meant a time in another zone, convert it first and type the local equivalent.
Does it keep running in the background?
It keeps ticking only while this page is open. A hidden tab may throttle the timer, so the display can stall and then jump. It does not use a server, and closing the page stops it.
What if the target is already past?
The result says Done. It does not show a negative timer or a count of elapsed time. Pick a later target and start again if you want a new countdown.