Count down to any date, run a duration timer with an alarm, or use the stopwatch with laps and fullscreen. Three tools, one page.
Timer
Pick a mode. Only one runs at a time.
Uses your device's local time zone.
Duration
h
m
s
An alarm sounds when the timer reaches zero. Keep the tab visible for the exact moment.
Lap
Split
Total
No laps yet. Press Lap while the stopwatch runs.
Countdown
--
Pick a mode on the left, set it up and press Start.
0days
0hours
0minutes
0seconds
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How the timing works
All three modes are driven by your device clock using millisecond timestamps, not by counting ticks, so they stay accurate even over long runs. The date countdown shows days, hours, minutes and seconds until your target. The duration timer counts down from the hours, minutes and seconds you set and plays an alarm at zero. The stopwatch counts up with tenth-of-a-second precision and records unlimited laps.
Tips for reliable alarms
Keep the tab visible: browsers throttle background tabs, which can delay the alarm.
Check your volume before starting a timer you depend on.
Fullscreen stopwatch is handy for classrooms, workouts and presentations. Press Esc to exit.
The timer is driven by your device clock with millisecond timestamps, so it stays accurate to about a second over long runs. Browsers slow down timers in background tabs, so keep the tab visible if the exact moment matters.
Will the alarm sound if the tab is in the background?
It depends on your browser. Most browsers throttle background tabs, which can delay the alarm by up to a minute. For a reliable alarm, keep the timer tab open and visible, and make sure your device volume is on.
What time zone does the date countdown use?
Your device's local time zone. The date and time you pick are interpreted exactly as shown on your device clock, so a countdown to midnight on New Year is midnight where you are.
Can I use the stopwatch in fullscreen?
Yes. Press the Fullscreen button under the stopwatch to fill the screen with the timer, which is handy for classrooms, workouts and presentations. Press Esc or the button again to exit.
Is there a limit on stopwatch laps?
No. You can record as many laps as you like. Each lap shows its split time and the running total, newest first.