Countdown Timer
Set hours, minutes, seconds. We count down and ring an alarm when time is up. Zero signup, works offline.
Why the alarm does not sound sometimes
Browsers block audio until you click somewhere on the page. Click Start first — after that the alarm will play even in a background tab. The alarm fires three short beeps using the Web Audio API, so it does not need an external sound file.
Ideas for using it
Boil an egg (7 min), steep tea (3–5 min), pomodoro focus (25 min work + 5 min break), rest between strength sets (90 sec), or never burn the cookies again. Keep this page open in a tab whenever you need a reliable countdown.
Frequently asked questions
Why did the alarm not go off?
You need to click <strong>Start</strong> once first — browsers block audio from pages the user has not interacted with. This is a browser security feature, not a bug.
How accurate is it?
Accurate to the second. We store an end timestamp and compare it to Date.now(), so browser throttling does not shift the moment it fires.
Can I run multiple timers?
Open multiple browser tabs — each tab is its own independent timer.
Does it drain battery?
Negligibly. We use a 250 ms interval which pauses when the tab is backgrounded, so there is no idle CPU burn.
Can I change the alarm sound?
Not yet — the beep is hardcoded as a 880 Hz sine wave through the Web Audio API. If you need louder, pair with a nearby phone alarm.
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