HIIT Timer

Picking your intervals

HIIT is not one protocol, it is a shape: hard work, real recovery, repeated. Everything else is a dial. The one that matters most is the ratio between work and rest, because it quietly decides what you are training.

• 1:2 — 30 on, 60 off. The most rest, and the best place to start. Enough recovery that round eight can be as hard as round one.
• 1:1 — 30 on, 30 off. The default here. A solid conditioning stimulus that most people can hold for ten rounds.
• 2:1 — 40 on, 20 off. Work starts to accumulate. Expect the last third to be noticeably harder than the first.
• 3:1 and beyond — 45 on, 15 off. Closer to a hard continuous effort with pauses in it. Useful, but not where to begin.

Which of those is right depends on whether you are chasing conditioning, power, or fat loss, and the honest answer is less dramatic than most articles claim. Choosing your work-to-rest ratio goes through what the evidence actually supports.

How to run it

1. Warm up for five minutes. Something that raises your heart rate gradually rather than all at once.
2. Set work, rest and rounds — or tap a preset. Total session time appears under the dial as you change them.
3. Press start. Ten seconds of countdown, then the timer runs the session: a tone at every switch, a tick over the final seconds, and the round number on screen the whole way.
4. Cool down. Two or three minutes of easy movement, then stretch if you are going to.

What to put in the work interval

Anything you can drive hard and repeat safely when tired. These need no equipment and no space to speak of:

• Burpees
• Mountain Climbers
• High Knees
• Jump Squats
• Skaters
• Jumping Jacks
• Jump Lunges
• Squats

If jumping is out — bad knees, a downstairs neighbour — the same shape works without it:

Ready-made sessions

If you would rather not design one, these are built and timed already, with every move illustrated:

For the four-minute version at the aggressive end of the scale, use the Tabata timer. For work that starts on the minute instead of after a rest, that is an EMOM.

Frequently asked questions

What is a good work-to-rest ratio for HIIT?

Start at 1:1 — 30 seconds of work to 30 seconds of rest. Move to 1:2 (30 on, 60 off) if you cannot keep the rounds comparable, and to 2:1 (40 on, 20 off) once you can. The ratio matters more than the absolute numbers.

How long should a HIIT session be?

Ten to twenty minutes of intervals, warm-up and cool-down aside. If you can comfortably do forty minutes of it, it was not high intensity — which is fine, but it is a different kind of training.

Is this HIIT timer free?

Yes, and there is no signup. It runs entirely in your browser. The iPhone and Apple Watch app is free as well, and calls the switches with voice and haptics.

Can I use this HIIT timer without rest intervals?

Yes — set rest to zero and the timer runs work intervals back to back, which is how an EMOM or a continuous circuit is usually clocked.

How many rounds of HIIT should I do?

Eight to twelve at a 1:1 ratio is a normal session. The useful test is whether your last round resembles your first; when it stops doing so, you have found the number.

Other timers

• Tabata TimerTwenty seconds of work, ten seconds of rest, eight times. Four minutes. Press start — the timer calls every switch so you never look at the clock.
• EMOM TimerEvery minute on the minute: the bell goes, you work, and whatever time you have left is your rest. Then it goes again.
• AMRAP TimerOne clock, counting down. You pick a circuit and get through it as many times as you can before it runs out. Nothing to decide once it starts.
• Circuit Training TimerForty-five seconds at a station, fifteen to get to the next one, twelve stations. One clock runs the whole room.
• Boxing Round TimerThree minutes on, one minute between, twelve rounds — the championship clock. Change it to whatever your gym runs.