The cycle this timer runs
Francesco Cirillo's Pomodoro Technique alternates focused work with short rests. This page defaults to 25 minutes of focus, a 5-minute short break and a 15-minute long break. You can set each in whole minutes (the fields are capped at 180, 60 and 90, and larger values you type are reduced to the cap), but they lock while the timer is running. Press Start and the clock counts down; at zero a beep plays (if Sound is ticked) and the next phase starts on its own, without another click. After each completed focus session the counter increases. Every fourth one is followed by the long break, and the "Until long break" box shows how many are left. Pause keeps the remaining time, and Reset returns to a full focus session and sets the counter to zero.
A full four-session cycle
| Step | Phase | Minutes |
|---|---|---|
| 1, 3, 5, 7 | Focus | 25 each (100 total) |
| 2, 4, 6 | Short break | 5 each (15 total) |
| 8 | Long break | 15 |
One complete round is therefore 130 minutes, with 100 of them spent focusing. While the timer is running, the browser tab title shows the live time and phase, such as 24:59 — Focus · Pomodoro. The original title is restored when you pause, reset or leave the page.
Background tabs and accuracy
The timer checks the clock a few times per second with setInterval. It does not count ticks; each update compares the current clock with the moment the phase is due to end. Browsers deliberately throttle timers in hidden tabs to save battery, and Chrome's "intensive throttling" can let a hidden page run its timers only about once a minute after several minutes in the background. Because the display is recalculated from the wall clock, the timer is still correct when you come back, and a phase that ended while the tab was hidden moves on to the right next phase (the beep plays when the page next runs). The beep itself is generated locally with the Web Audio API. Practical advice:
- Keep the Pomodoro tab in its own window that stays visible next to your work, or pin it as a tab and glance at it regularly.
- The beep may arrive late in a heavily throttled tab, but the displayed time stays correct.
- Closing the tab or reloading erases the timer, the settings and the session count; nothing is stored.
Choosing the lengths
- 25/5/15 suits routine tasks and study.
- 50/10/30 gives longer blocks for programming or writing, where getting back into context is costly.
- If a break ends mid-thought, extend the focus length rather than skipping breaks.
For a one-off deadline instead of repeating intervals, try the countdown timer.