Countdown Timer
Free countdown timer. Set any duration in hours, minutes, or seconds with audible alarm at zero. Perfect for cooking, presentations, and workouts.
Quick answer
Set hours, minutes, and seconds, then press start. The timer counts down to zero and triggers a sound (browser permission required). Refresh the page to reset. Background tabs may throttle the visible countdown but the underlying timer fires on time.
Countdown Timer
How it works
Set hours, minutes, and seconds, then start. The timer counts down to zero and alerts you. The browser tab title also shows the remaining time so you can see it from another tab.
When to use it
Cooking, presentations, board games, kid time-outs, intervals during workouts, or any task with a hard deadline.
Common mistakes
Closing the tab — the timer pauses if the tab is fully unloaded. Browsers throttle JavaScript timers in background tabs, so the actual time may run a few seconds slow if you switch away. Use a phone alarm for anything truly mission-critical.
How the countdown timer works
The timer schedules a single setTimeout for the target duration. The display polls the remaining time at animation-frame rate (~60fps) for smooth visual countdown. When the underlying timer fires, an alarm sound plays via the Web Audio API. Modern browsers throttle setInterval/setTimeout in inactive tabs to ~1Hz, so the visible countdown may slow when you switch tabs — but the actual fire time is preserved within seconds of the target.
When to use it
Cooking — meal-prep timers, Pomodoro cycles, baking. Workout intervals where you don't need a dedicated app. Presentations and pitch practice — set a 5-minute timer and practice cutting to length. Tea steeping (sub-3-minute tasks where you'll forget without a beep). Kid screen time, quiet time, or transition warnings.
Common mistakes
- Forgetting browser sound permissions. Many browsers block autoplay audio until you've interacted with the page. Click 'start' once first to grant the permission.
- Closing the tab. Closing the tab kills the timer. Move to a dedicated phone or desktop alarm if you need to walk away.
- Trusting it for safety-critical timing. Browser timers can drift several seconds for long durations in inactive tabs. For anything where precision matters (e.g., medication reminders), use a dedicated app or hardware timer.
Frequently asked questions
Does the timer keep running if I switch tabs?
Yes — the underlying setTimeout fires regardless of tab focus. The visible countdown may slow in inactive tabs (browsers throttle background timers) but the alarm fires at the right time.
Will the timer make a sound when it ends?
Yes, if your browser allows audio. You may need to click 'start' once first to grant audio permission. The alarm uses the Web Audio API and works in all modern browsers.
Can I set a timer longer than an hour?
Yes. The countdown supports any number of hours, minutes, and seconds. For very long timers (multiple hours), expect minor drift in inactive tabs — usually within a few seconds of the target.