Stopwatch & Timer

The Pomodoro technique, done properly

The Pomodoro Technique, devised by Francesco Cirillo in the late 1980s, breaks work into fixed focus blocks separated by short breaks. The classic recipe is 25 minutes of single-tasking, then a 5-minute break; after four such 'pomodoros' you take a longer 15-30 minute break. The point isn't the exact 25 minutes — it's the commitment that for one timer's length you do one thing and ignore everything else, and that the break is mandatory, not optional. A countdown timer is the entire apparatus the method needs.

The 25/5 split is a starting default, not a law. Deep work often suits 50/10; people who find 25 minutes too short to get into flow lengthen the block, while those who stall extend the break. Treat the numbers as dials. For a dedicated focus-cycle interface with automatic break tracking, the Pomodoro Timer is purpose-built; this tool is the flexible general-purpose version.

Interval training and other timed work

• HIIT and Tabata: Tabata is a specific protocol — eight rounds of 20 seconds all-out, 10 seconds rest, totalling exactly 4 minutes. Other interval formats (30/30, 40/20, EMOM 'every minute on the minute') just change the numbers.
• Cooking and brewing: a steeping tea or a soft-boiled egg cares about seconds, and a countdown that survives a backgrounded tab means you don't burn dinner because you switched apps.
• Public speaking and exams: rehearsing to a hard time limit, or pacing yourself through a timed test, is exactly what a visible countdown is for.
• Stretching, plank holds and rest periods between lifts: short repeated intervals where glancing at a clock breaks your form.

Why browser timers drift — and how this one doesn't

Browsers deliberately slow down inactive tabs to save battery and CPU. A timer built on a naive ticking counter — 'add one second every second' via setInterval — gets throttled when its tab loses focus, so it falls behind and under-reports the time that actually passed. This is documented browser behaviour: background tabs have their timers clamped, and the effect is worse on mobile and when the screen is locked. It's the reason so many web timers are mysteriously 'slow' if you look away. The MDN reference on timer throttling covers the detail.

The correct fix, which this tool uses, is to record the absolute target timestamp at the moment you press Start and compare it to the real clock whenever the page wakes up — so the countdown is accurate the instant you return to the tab, regardless of how long it was throttled. The end-sound fires based on that wall-clock target, not on a count of frames the browser may have skipped. The one thing no web page can guarantee is firing a sound while the tab is fully suspended on some mobile OSes; bring the tab to the foreground for anything mission-critical.