How long is one Tabata block?

Four minutes. Eight intervals of twenty seconds of work and ten seconds of rest come to exactly two hundred and forty seconds.

Why does the clock stop on the last work interval?

The eighth rest has nothing after it, so counting it down would just be ten seconds of standing still after the workout ended. The four minutes of protocol are all there.

Which exercises suit Tabata?

Simple, repetitive movements that stay safe while you are tired. Squats, mountain climbers, kettlebell swings and jumping jacks work. Heavy or technical lifts do not, because form fails at exactly the moment the clock tells you to keep going.

Can I run more than four minutes?

Yes. Raise the interval count and the block gets longer, or add stations and each one gets its own four minutes with a recovery between them.

Timer

Tabata timer

Twenty seconds of work, ten seconds of rest, eight times through. The protocol is fixed, so the timer only asks how many blocks you want.

The timer

Intervals

Lead-in

Stations, one per line

Named stations appear on the clock as they come up. Leave it as it is to run one unnamed block.

The clock runs fullscreen and keeps the screen awake. It needs JavaScript, so with scripting off the plan below is the whole session written out.

Total: 4:00
Working: 2:40
Periods: 16

01ReadyGet ready0:10
02WorkWork0:20
03RestRest0:10
04WorkWork0:20
05RestRest0:10
06WorkWork0:20
07RestRest0:10
08WorkWork0:20
09RestRest0:10
10WorkWork0:20
11RestRest0:10
12WorkWork0:20
13RestRest0:10
14WorkWork0:20
15RestRest0:10
16WorkWork0:20

How it works

Tabata is twenty seconds of hard work followed by ten seconds of rest, repeated eight times, for four minutes in total. The numbers are the protocol, so this timer does not ask you to choose them. It asks how many blocks you want and then counts.

Press start and the clock gives you a ten second lead-in, then runs the eight intervals with a beep before every change. The interval count is on screen throughout, because knowing you are on round five of eight is the difference between pacing and guessing.

Four minutes is one block on one exercise. A full session stacks three to five blocks with a minute of recovery between them, which lands between fifteen and twenty-five minutes. Add a station for each block and the timer names the movement as it comes up.

Ten seconds is not long enough to recover, and that is the mechanism the protocol runs on. Every interval starts more tired than the last, so the work rate you pick in round one decides whether rounds five through eight are hard or impossible. Go slightly below your maximum at the start. The aim is eight consistent rounds.

The reputation of Tabata as a quick workout does it no favors. Done at the effort the research used, four minutes is genuinely brutal and does not leave much for the rest of the session. Put it at the end of a training day, not the start.

Questions

How long is one Tabata block?: Four minutes. Eight intervals of twenty seconds of work and ten seconds of rest come to exactly two hundred and forty seconds.
Why does the clock stop on the last work interval?: The eighth rest has nothing after it, so counting it down would just be ten seconds of standing still after the workout ended. The four minutes of protocol are all there.
Which exercises suit Tabata?: Simple, repetitive movements that stay safe while you are tired. Squats, mountain climbers, kettlebell swings and jumping jacks work. Heavy or technical lifts do not, because form fails at exactly the moment the clock tells you to keep going.
Can I run more than four minutes?: Yes. Raise the interval count and the block gets longer, or add stations and each one gets its own four minutes with a recovery between them.