HIIT Timer

How to use the HIIT timer

This HIIT timer gives you ready-made interval workouts: tap a preset like 40/20 × 10, press Start, and it counts down every work and rest period with a beep at each change. A "get ready" countdown, colored phases and a round counter keep you on track without stopping to check your watch.

HIIT, or high-intensity interval training, means short, hard efforts alternated with periods of recovery. The work should feel tough enough that you couldn't keep it up for long; the rest lets you recover just enough to go hard again.

1. Pick a preset below, or edit the work, rest and round values.
2. Check the prep countdown so you have time to get set before round 1.
3. Press Start or the Space bar, then work until the beep and the color change tell you to rest.
4. Listen for the 3-2-1 countdown at the end of each rest so you're ready to go again.

HIIT presets at a glance

Preset	Work / rest	Rounds	Interval time	Best for
30/30 × 10	30 s / 30 s	10	About 10 min	Beginners and recovery days; equal work and rest
40/20 × 10	40 s / 20 s	10	About 10 min	The classic HIIT interval timer setup for circuits
45/15 × 8	45 s / 15 s	8	About 8 min	Experienced exercisers who want long efforts and short recovery

The presets are starting points. Every value can be edited, so you can add rounds, stretch the rest or build your own format.

A beginner-to-advanced HIIT progression

Progress by changing one thing at a time: first add rounds, then shorten the rest. A simple plan over several weeks might look like this:

• Stage 1: 30/30 × 6–8. Choose moves you can do with good form, like marching high knees, bodyweight squats and incline push-ups.
• Stage 2: 30/30 × 10. Same length of work, more rounds.
• Stage 3: 40/20 × 10. More work, less rest — this is where most people settle.
• Stage 4: 45/15 × 8, or two blocks of 40/20 × 10 with a few easy minutes in between.

Two or three HIIT sessions a week with easier days in between is a common approach. If your form falls apart in the last rounds, go back a stage.

Sample 40/20 circuit

Repeat this five-move circuit twice for the 10 rounds of the 40/20 preset. Use each 20-second rest to move to the next exercise.

1. Jump squats (or regular squats)
2. Mountain climbers
3. Push-ups (from knees or an incline if needed)
4. Alternating reverse lunges
5. Burpees (or squat thrusts without the jump)

Warm up first and stay safe

Spend 5 to 10 minutes warming up with easy movement, such as brisk walking, light jogging or arm circles, before your first hard interval, and cool down with easy movement afterward. If you have a heart condition or other health concerns, talk to your doctor before starting vigorous exercise.

Tabata, intervals and more

Looking for the 20-second protocol? The Tabata timer is set to 20 seconds on and 10 off for 8 rounds. For fully custom formats like EMOMs, use the custom interval timer, and for 3-minute rounds with a bell, try the boxing timer.

Frequently asked questions

Which HIIT preset should I start with?

Start with 30/30 × 10, or fewer rounds if 10 is too much. Equal work and rest gives you time to recover and focus on form before you move to 40/20.

Can I hear the beeps over my music?

Try a few of the sounds in the list to find one that cuts through your playlist, and keep your music at a level where you can still hear the phone. You can also mute the sound and follow the phase colors on screen instead.

Will my phone screen turn off mid-workout?

The HIIT timer asks the browser to keep the screen awake while it runs, but on phones this depends on your browser. Time stays accurate either way, though sounds only play while the page is open.

Can I do a longer HIIT workout?

Yes. Increase the rounds on any preset, or run the timer again after a few minutes of easy movement to do a second block.