Interval Timer for HIIT & Tabata
Pick Tabata, HIIT, EMOM or boxing rounds, or set your own work and rest times, rounds and sets. The big color-coded display shows green for work and amber for rest, and beeps and voice cues count you into every interval.
Times are minutes:seconds (e.g. 1:30) or plain seconds (e.g. 45). Settings are applied when the timer is reset.
Shortcuts: Space start / pause · N skip phase · R reset · F fullscreen.
How to use the Interval Timer for HIIT & Tabata
- Choose a preset such as Tabata or HIIT, or type your own warm-up, work and rest times (for example 0:45 or 45).
- Set rounds and sets. With more than one set, the rest between sets replaces the last rest of each set.
- Check the summary for the total workout time and optionally save the settings as your own preset.
- Press Start workout (or Space). Beeps and voice cues tell you when each interval starts and count down the last 3 seconds.
- Use Pause, Skip or Reset at any time, and Fullscreen to see the timer from across the room.
Popular interval formats
| Format | Work / rest | Rounds | Work time | Total time |
|---|---|---|---|---|
| Tabata | 20 s / 10 s | 8 | 2:40 | 4:00 (the last rest is skipped by this timer: 3:50) |
| HIIT 40/20 | 40 s / 20 s | 10 | 6:40 | 10:00 (9:40 without the final rest) |
| HIIT 30/30 | 30 s / 30 s | 10 | 5:00 | 10:00 (9:30 without the final rest) |
| EMOM | 60 s blocks | 10 | – | 10:00 |
| Boxing (pro) | 3:00 / 1:00 | 12 | 36:00 | 47:00 |
| Boxing (amateur) | 3:00 / 1:00 | 3 | 9:00 | 11:00 |
The timer does not add a rest after the very last work interval, because the workout is finished at that point. It also adds the warm-up and cool-down you set, so the total shown in the summary is the real time from Start to the final beep.
How total time is calculated
For R rounds and S sets: total = warm-up + S × R × work + S × (R − 1) × rest + (S − 1) × rest between sets + cool-down. Example: 3 sets of 8 rounds of 40/20 with 1:00 between sets and a 0:30 warm-up gives 0:30 + 24 × 0:40 + 21 × 0:20 + 2 × 1:00 = 0:30 + 16:00 + 7:00 + 2:00 = 25:30.
Tips for interval training
- Warm up first. A few minutes of easy movement raises your heart rate and reduces injury risk before hard intervals.
- Match the ratio to your goal. Short rest (2:1 work-to-rest such as 40/20) builds conditioning; longer rest (1:1 or 1:2) lets you keep the quality high for sprints or heavy lifts.
- Use sets to organise circuits. For example, 4 exercises as 4 rounds per set and 3 sets with 1:30 rest between them.
- Listen instead of looking. With voice cues on you can keep your eyes on your form; the 3-2-1 countdown tells you exactly when to switch.
- Progress gradually. Add a round, shorten the rest by 5 seconds or extend the work interval each week rather than all at once.
- Check with a professional before starting high-intensity training if you have heart, blood pressure or joint problems.
Frequently asked questions
What is a Tabata workout?
Tabata is a form of high-intensity interval training with 20 seconds of all-out effort followed by 10 seconds of rest, repeated 8 times for a total of 4 minutes. It is named after Dr Izumi Tabata, whose 1996 study used this protocol on a cycle ergometer.
What is the difference between HIIT and Tabata?
HIIT (high-intensity interval training) is the general method of alternating hard work with recovery. Tabata is one specific HIIT protocol (20/10 × 8). Other common HIIT formats are 40 seconds on / 20 seconds off, 30/30 or 45/15.
How does EMOM work with this timer?
EMOM means every minute on the minute: at the start of each minute you do a set number of reps, and the rest of the minute is your recovery. The EMOM preset uses 60-second work intervals with no separate rest, and a beep and voice cue mark the start of each new minute.
How long are boxing rounds?
Professional boxing rounds last 3 minutes with 1 minute of rest between rounds, which is what the boxing preset uses (12 rounds). Amateur bouts often use 3 rounds of 3 minutes, and many training sessions use 2-minute rounds.
Why can't I hear the voice cues?
Voice cues use your browser's built-in speech synthesis. Make sure the device is not muted and that Voice cues is ticked. Some browsers need a moment to load voices the first time, and a few do not support speech at all; the beeps still work.
Will my screen turn off during the workout?
When Keep screen awake is ticked, the timer asks the browser for a screen wake lock while the workout runs. This works in most current browsers on phones and computers; if it is not supported, change your device's auto-lock setting during workouts.
Are my custom presets saved?
Yes, saved presets are stored in your browser on this device, so they are still there next time you open the page. They are not uploaded anywhere.