20s work / 10s rest × 8 rounds
Tabata Timer
Twenty seconds hard, ten seconds rest, eight rounds — the original four-minute protocol.
Tabata
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Frequently asked questions
- Is Tabata the same as HIIT?
- Tabata is one very specific form of HIIT — 20 seconds on, 10 off, eight rounds, at maximal effort. HIIT is the broader category and covers any work/rest interval structure. Every Tabata is HIIT; most HIIT is not Tabata.
- Why is it only four minutes?
- Eight rounds of 20 seconds work plus 10 seconds rest is exactly four minutes — the full protocol from the original study. The intensity is what makes it effective, not the length, so adding rounds usually just means you were not going hard enough.
- What exercise should I use?
- Ideally one movement you can push to near-maximal effort safely — a bike, rower, or sprints. Bodyweight moves like squats or burpees work too, but avoid complex lifts where fatigue wrecks your form by round five.
- Can I change the rounds or the timings?
- Yes — adjust work, rest, and rounds before you start, and share the result with the copy-link button. Just know that once you deviate from 20/10 × 8 you are doing interval training, not the studied Tabata protocol.
- Will the sounds work if my screen turns off or I change apps?
- While the tab stays open and in front, the work and rest cues fire on time. Switch apps and a backgrounded tab can delay them by up to a minute; lock the phone or let the screen sleep — especially on an iPhone — and the alert may not fire at all. Keep the tab visible with the screen awake, and on iPhone the mute switch off.
This timer keeps the exact time even if you switch tabs. If this tab or your browser closes, nothing can alert you at the exact finish time — there's no server behind this, by design. Come back any time and we'll tell you honestly how long ago it ended.