Online Countdown Timer
Set your time and press start. It rings the moment time is up — even in a background tab.
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Is the timer accurate when the tab is in the background or minimized?
Yes. Instead of counting ticks, this countdown timer stores the exact end time when you press start and recomputes the time left from the clock on every update. Even if the browser throttles background tabs, the correct time shows the moment you return — and if the end time has already passed, the alarm rings immediately.
I can't hear the alarm — why, and how do I fix it?
Browsers only allow sound after you interact with the page, so this online timer arms the sound the moment you press Start. If you still hear nothing, check the system volume, the tab's mute setting and the silent switch on phones. If your browser doesn't support Web Audio, a notice appears and the alert stays visual only.
How do I use the 1/3/5/10/30 minute presets for cooking, studying or workouts?
One tap sets a common time: 3 minutes for instant noodles or tea as a cooking timer, a 5 minute timer for breaks and stretching, 10 minutes for a short study sprint, 30 minutes for a focus session or workout. After a preset just press Start — your last setting is restored on your next visit.
What's the difference between a stopwatch and a countdown timer?
A stopwatch counts up from zero to measure how long something takes. A countdown timer does the opposite: you set a duration, it counts down to zero and then rings. Use a stopwatch to record times, and a timer with alarm to be reminded.
Does it keep working if the internet disconnects?
Yes. Once the page is loaded, everything runs inside your browser and nothing is sent to a server. A running online timer keeps counting down and rings even while offline, and you can install it as a PWA for offline use.