Online countdown timer
Ready to start
Sound not tested. Check your volume and output device.
What to expect
Keep this page visible and your device awake for a timely alert. Browsers can delay or stop sound in background tabs, during sleep or when the screen locks. Timer and sound help.
Refresh restores the timer in this tab when session storage is available. An old or missed alarm is shown without playing sound. Reset clears the saved timer.
A timer for the task in front of you
Choose a preset or set hours, minutes and seconds, from 1 second to 24 hours. Start the countdown, pause whenever you need to, then resume with the time you had left. Reset unlocks the duration fields.
The timer uses your device’s clock. It recalculates the remaining time after delayed updates, so missed screen updates do not accumulate into drift. Changing the system clock can change the remaining time.
Fullscreen uses the same controls in a larger view. A shared duration opens ready to start; it does not share your running timer.