How the cycle runs
A focus session (25 minutes unless you change it) is followed by a short break (5 minutes). After the fourth focus session the break is a long one (15 minutes), and the set starts again. The dots show where you are in the set: a filled dot is a focus session done. A chime sounds at each change, and the tab's title shows the phase and the minutes left, such as 18:42 · Focus.
Your own lengths
Change the minutes for focus, short and long breaks, and how many focus sessions make a set, while the timer is stopped. With Auto-start on, each phase starts the next without waiting; with it off, the timer stops at each change and waits for you to press Start. Skip moves on to the next phase straight away, and counts a skipped focus session as done. The tabs along the top jump to any phase.
A link that keeps your settings
Nothing is stored on your device. Instead the lengths go in the address, as focus, short and long minutes and then the set size: /pomodoro-timer#50-10-30-3 opens with 50 minute sessions, 10 minute breaks and a 30 minute long break after every third. Bookmark it, and the timer opens set up your way.
In a background tab, or asleep
The timer keeps the moment each phase ends and works out what is left from your device's clock, so it stays right while you work in another tab. Browsers slow down hidden pages, so it checks the clock from a small background worker they leave alone, and the chime comes within a second of the change. While it runs it asks the browser to keep the screen on. If the computer sleeps anyway, the timer catches up from the system clock when it wakes, moving through any phases that ended while it slept if Auto-start is on.
Questions
What is the Pomodoro Technique?
A way of working devised by Francesco Cirillo in the late 1980s, named after his tomato-shaped kitchen timer. You pick one task, work on it for 25 minutes without switching, then take a short break; after four of these you take a longer one. Short, fixed stretches make a big task easier to start and keep breaks from being skipped.
What if I am interrupted?
Press Pause and pick up where you left off, or Reset to start the session again. The technique's own rule is that an interrupted session does not count, but the timer leaves that to you.
Why did I not hear the chime?
Check that Sound is on and the device is not muted. Browsers only let a page make sound after you have pressed something on it, which pressing Start does.