Yes. The timer tracks wall-clock time rather than counting JavaScript ticks, so it stays accurate even when the tab is in the background. Browsers throttle JavaScript timers in background tabs, which would cause a simple tick-counter to drift. This timer compensates by measuring actual elapsed time from when the session started.
Yes. The timer settings let you adjust the work interval (default 25 minutes), short break (default 5 minutes), and long break (default 15 minutes). Changes take effect at the start of the next session. The only thing the Pomodoro Technique asks is that you respect whatever interval you choose while it's running — the benefit comes from committed, uninterrupted focus blocks.
25 minutes is Cirillo's original default, not a scientifically prescribed length. Many people find 45 or 50 minutes more appropriate for deep work tasks (writing, coding, analysis). Others use 20 minutes for tasks that require intense but shorter bursts. The tool supports any interval from a few minutes to 90 minutes. Try the default first, then adjust based on how it feels after a week.
Browsers require user interaction before they'll play audio. If you load the page and leave it without clicking anything, the browser may block the notification sound. Clicking Start counts as user interaction, so the sound should play when a session ends as long as you clicked to begin it. Also check that your device volume is on and the tab isn't muted (right-click the tab in Chrome or Firefox to check).
After four completed work sessions, the timer automatically starts the long break period (default 15 minutes, adjustable). After the long break, the cycle resets to session 1. The session counter on screen shows where you are in the cycle at all times.
The Pomodoro Technique says yes — end the session, take the break, and return. The argument is that flow states feel productive but can mask diminishing returns, and the break time is when the brain consolidates what it just processed. In practice, many people override this when they're deeply embedded in a problem. That's fine occasionally, but if you find yourself skipping breaks every session, the technique isn't working as designed.
Yes. The timer is responsive and works on mobile browsers. The main limitation on mobile is that iOS aggressively suspends tabs that aren't in the foreground — the timer may not sound the alert if the tab is in the background for an extended period. For reliable mobile use, keep the tab in the foreground or install the site as a PWA if your browser offers that option.