Time your intervals.

A Tabata interval is a set structure of 20 seconds of hard work followed by 10 seconds of rest, repeated for 8 rounds, which comes to 4 minutes total. It started as a research protocol run by Dr Izumi Tabata on the Japanese speed skating team, where the work bouts were done at a very high effort. On this timer the Tabata preset loads those numbers for you, and you can still open the custom builder if you want a different split.

EMOM stands for every minute on the minute. You start a new set of reps at the top of each minute, do your prescribed work, then rest for whatever time is left until the next minute begins. A round with fewer reps buys you more rest, so the pace is self scaling. Set the number of minutes on this timer and it will chime at the top of each one so you always know when to go again.

AMRAP stands for as many rounds or reps as possible. You pick a single time window, say 12 minutes, and work through a chosen set of movements without stopping, scoring how much you finish before the clock runs out. This timer runs AMRAP as one window that either counts up so you can see time spent or counts down to zero, whichever you prefer. Pick the length, hit start, and go until it ends.

Yes. The timer tracks each phase against a real clock rather than counting ticks, so when the tab is throttled in the background it does not fall behind. When you come back to the page it recomputes where you should be and jumps straight to the correct phase and time remaining. On phones the screen wake lock keeps the display on while a workout runs, and it reengages on its own if you leave and return.

Browsers block sound until you interact with the page, which stops sites from playing audio at you uninvited. Pressing start counts as that interaction, so the timer waits until then to switch its audio on. After the first start you get a tone at each phase change, three short ticks in the final seconds of a phase, and a finish sound at the end. If your browser has no audio support the timer runs silently and everything else still works.

Yes. Choose Custom and set your own work seconds, rest seconds, and number of rounds. You can also group rounds into sets and add a longer rest between each set, which suits circuits where you run through a block of movements, breathe, then run the block again. Your last setup is saved in this browser and loads again next time you open the page, so a routine you use often is ready to start.