Pomodoro Timer

How to use Pomodoro Timer

1. Press start to begin a 25-minute focus interval, or adjust the durations first.
2. Work until the timer sounds, then take the break it offers.
3. After four cycles, take the long break. The session counter tracks your completed intervals.

What is the Pomodoro Technique?

A time management method developed by Francesco Cirillo in the late 1980s, named after the tomato-shaped kitchen timer he used as a student.

The structure is fixed: 25 minutes of single-task work, a 5-minute break, repeated four times, then a 15–30 minute long break. One 25-minute interval is a "pomodoro" and is treated as indivisible — if you are interrupted, the pomodoro is void rather than paused.

The mechanism is less about the specific durations than about two things. First, it makes starting easier, because committing to 25 minutes is psychologically cheaper than committing to a task of unknown length. Second, it enforces breaks that people otherwise skip, and skipped breaks are what turn a productive morning into an unproductive afternoon.

Do the standard durations work for everyone?

No, and treating 25/5 as sacred is the most common way people bounce off the technique.

The 25-minute figure was chosen because it suited Cirillo's own studying. Work requiring deep context — writing, complex debugging, mathematical reasoning — has a warm-up cost of ten to fifteen minutes before full engagement, and a 25-minute cap interrupts it just as it becomes productive. 50/10 or 90/20 suits that work far better.

Shallower work with natural break points — email, code review, admin, data entry — fits 25/5 well, and shorter intervals can help when concentration is difficult.

The 90-minute figure has some grounding: the ultradian rhythm literature suggests human alertness cycles on roughly a 90-minute period. The evidence is suggestive rather than conclusive, but it matches many people’s experience.

Why do browser timers drift, and how is this one accurate?

Because browsers throttle background tabs to save battery. A setInterval running at one second is clamped to once per minute or slower in a hidden tab, and a naive timer that counts ticks will run minutes late over a 25-minute interval.

Two techniques fix it, and this timer uses both. The countdown is computed from a wall-clock timestamp taken at start — so however irregularly the tick fires, the remaining time is always calculated from the actual elapsed duration rather than accumulated. And the tick itself runs in a Web Worker, which is throttled far less aggressively than the main thread.

The result is accurate to within a second over a full interval regardless of whether the tab is visible, which is the entire point of a timer you start and then switch away from.

What should you do during the break?

Something that is not a screen. This is where most attempts at the technique fail.

The break exists to let the attention system recover, and scrolling a feed for five minutes does not do that — it substitutes one demanding visual task for another. Standing up, walking, looking at something more than six meters away, getting water, or doing nothing at all all work considerably better.

The distance-viewing point has a physiological basis: sustained near-focus fatigues the ciliary muscle, and the 20-20-20 guidance from optometry bodies — every 20 minutes, look at something 20 feet away for 20 seconds — maps almost exactly onto a Pomodoro break. Taking the break at a window is a genuinely better use of it than taking it at your phone.

Frequently asked questions