Quick Presets
How to Use
- Set the duration
Enter the hours, minutes, and seconds for your countdown.
- Start the timer
Click the Start button to begin the countdown. You can pause and resume at any time.
- Receive the alert
When the countdown finishes, you will be notified with a sound and visual alert.
What is a Countdown Timer?
A countdown timer is a tool that displays time counting down in real time from a value you set toward zero. While an ordinary clock runs by adding time, a countdown subtracts as it goes, giving you an intuitive sense of the time remaining until a deadline.
This timer supports two modes. The direct duration mode lets you specify hours, minutes, and seconds, or pick a preset (1 minute, 5 minutes, a 25-minute Pomodoro, and so on) to measure a fixed length and start instantly. The target time mode lets you set a specific date and time; the difference from the current moment is calculated automatically and the timer counts down to that point.
- Cooking and workouts: accurately time boiling pasta, rest intervals, and more
- Focus and study: repeat the Pomodoro cycle of 25 minutes of focus plus 5 minutes of rest
- Events: exam end, presentation limits, time left until a deadline
Calculation Formula
The direct duration mode converts hours, minutes, and seconds into total seconds.
total seconds = hours × 3600 + minutes × 60 + seconds
For example, 1 hour 25 minutes 30 seconds becomes 1×3600 + 25×60 + 30 = 5,130 seconds. On screen this is converted back to the HH:MM:SS format and shown as 01:25:30.
The target time mode converts the milliseconds left after subtracting the current time from the target time into seconds.
seconds remaining = ⌈(target time − current time) ÷ 1000⌉
If the target is already in the past, it is treated as 0 seconds. The display refreshes every second (1000 ms).