Where the technique came from
Francesco Cirillo’s method from the late 1980s, named after the tomato-shaped kitchen timer he used: twenty-five minutes of single-task work, a five-minute break, and a longer break after four cycles.
The specific numbers matter less than the two rules behind them. One task per interval, and the break is actually taken — a break spent on another screen is not a break.
Adjusting the intervals
Twenty-five minutes is short for work that takes a while to get into. Programming, writing and analysis often suit 45 or 50 minutes with a ten-minute break, because the cost of interrupting a deep task is higher than the benefit of a frequent pause.
Shorter intervals suit tasks you are avoiding. Fifteen minutes is easier to start than an hour, and starting is usually the problem.
It stays accurate in the background
Browsers throttle inactive tabs, so timers that count ticks fall behind. This one stores the target time and reads the clock, which is the difference between a timer you can leave in another window and one you cannot.
Frequently asked questions
Why 25 minutes?
It is what Cirillo used with a kitchen timer in the 1980s. The number is less important than the two rules: one task per interval, and take the break.
Can I change the intervals?
Yes. Deep work often suits 45 or 50 minutes; tasks you are avoiding suit fifteen, because starting is the hard part.
Does it drift in a background tab?
No — it reads the clock rather than counting ticks, so throttling does not affect it.
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