Countdown Timer

Count down from a chosen hours, minutes, and seconds duration with start, pause, and reset controls — includes an alert on completion.

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00:05:00

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Online Timer

Countdown timer online: set hours, minutes, seconds with alert

The online countdown timer counts down from a duration you set — in hours, minutes, and seconds — and plays an alert when time runs out. With start, pause, and reset controls plus a completion notification, it is perfect for cooking, exercise intervals, study sessions (Pomodoro technique), presentations, and any timed activity.

How the countdown timer works

Enter the hours, minutes, and seconds you want to count down from. Press Start and the timer begins decrementing by one second every second using the browser's interval timer. The display updates in real time showing the remaining time in H:MM:SS format. Pause freezes the countdown at the current value; pressing Start again resumes from where it stopped. Reset returns the timer to the originally entered duration.

When the display reaches 00:00:00, the timer fires a completion alert — an audible beep or chime (subject to browser audio permissions) and a visual on-screen notification. The timer does not go below zero; it holds at 00:00:00 until you reset it.

Remaining (s) = Set duration (s) − Elapsed time (s)

Decremented by 1 each second; alert fires when remaining reaches 0.

Popular uses for countdown timers

The Pomodoro technique uses a 25-minute countdown for focused work followed by a 5-minute break. Set the timer to 25:00, work without distraction until it fires, then reset to 05:00 for the break. Repeat four cycles then take a longer 15–30 minute break.

For cooking, set the timer to the recipe's stated cooking time as soon as you start the oven or stove. For exercise intervals such as HIIT, use repeated countdowns matching your work and rest periods. For presentations and speeches, set the timer to your allotted speaking time and glance at it periodically to pace yourself.

Frequently asked questions

Can I pause and resume the countdown timer?

Yes. Pressing Pause stops the countdown at the current remaining time. Pressing Start again continues from that point. The timer remembers exactly where it stopped, so no time is lost during a pause.

 Does the timer work if I switch browser tabs?

The countdown continues to run in the background even if you switch to another tab. However, some browsers throttle background tab timers, which can cause the displayed time to lag slightly when you return. The alert will still fire when time expires.

 What is the Pomodoro technique and how long should I set the timer?

The Pomodoro technique is a time-management method where you work in focused 25-minute blocks separated by 5-minute breaks. After four consecutive work blocks (pomodoros), take a longer break of 15–30 minutes. Set the countdown timer to 25:00 for work sessions and 05:00 for short breaks.

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