Tabata Timer

What is Tabata 20/10

Twenty seconds of work, ten seconds of rest, eight rounds in a row — the whole thing takes four minutes. These numbers come from the research of Izumi Tabata and his colleagues. In the study, subjects pedaled an ergometer seven or eight rounds of 20 seconds with 10 seconds of rest at an intensity of about 170% of maximal oxygen uptake.

The fields are pre-filled with the protocol numbers: 10 seconds of preparation, 20 of work, 10 of rest, eight rounds. Press "Start" and the timer walks you through the rounds on its own, naming the current phase, showing the round number and how much time is left until the end of the workout.

Custom intervals from the keyboard

Preparation, work, rest, rounds, cycles, and the break between cycles are plain fields where you type a number, and the total length of the workout shows right next to them. Other timers make you change these values with "plus" and "minus" buttons one second at a time, so setting your own numbers there takes a while.

The count never drifts

Time is measured by clock timestamps instead of subtracting one second on every frame, so a collapsed tab or a locked screen does not affect the count. While a workout is running, the page keeps the screen awake, and the settings and current round are stored in the browser: after a reload, the timer picks up from the same second. For a plain count without rounds, use the online stopwatch.