A countdown timer changes behaviour in a way a clock does not. A visible, shrinking number creates a mild deadline pressure that keeps attention on the task, and it removes the need to keep checking how long is left. That is why timers are central to nearly every focus technique, every kitchen, and every classroom activity that has to end on time.
The timer runs in your browser and keeps running while the tab is in the background, with an alert when it reaches zero.
Durations that work
| Duration | Use | Why it works |
|---|---|---|
| 2 minutes | Anything you have been avoiding | Short enough that starting is easy |
| 5 minutes | Tidying, warm-ups, transitions | Fits between other activities |
| 15 minutes | Focused single task, exam sections | Sustains attention without fatigue |
| 25 minutes | Pomodoro work block | The most-tested focus interval |
| 50 minutes | Deep work for practised users | Suits tasks with long setup time |
| 90 minutes | Full ultradian cycle | Matches natural alertness rhythm |
The Pomodoro technique
Twenty-five minutes of work, a five-minute break, repeated four times, then a longer break of fifteen to thirty minutes. The value is less in the specific numbers than in the enforced stopping: breaks taken on a timer actually happen, whereas breaks taken "when I finish this" tend not to. If twenty-five minutes cuts across your work awkwardly, lengthen the block — the structure survives the adjustment.
Beyond focus work
- Cooking: multiple steps with different finish times, without relying on memory.
- Interval training: work and rest periods that need to be consistent to be comparable.
- Classrooms: activity rotations and timed tests, where a visible timer reduces the number of "how long left?" interruptions.
- Meetings: a timer per agenda item is the most effective way to shorten a meeting.
- Presentation practice: rehearsing to the actual time limit rather than an estimate.
Making the timer reliable
Keep the tab open — closing it stops the timer. Enable notifications if you plan to switch away, and check that your device is not on silent before relying on the sound. For anything where missing the end has real consequences, such as cooking, a second alarm on your phone costs nothing and covers the case where a browser tab is suspended by an aggressive power-saving setting.
Related tools
- Online Stopwatch — counting up instead
- Classroom Timer
- Time Calculator
- Browse all free tools