Free HIIT Timer
No app. No signup. Just HIIT it.
Work 20s · Rest 10s · 8 rounds
Start TimerWhy JustHIIT It?
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What is HIIT?
High-Intensity Interval Training (HIIT) alternates short bursts of intense exercise with brief rest periods. A typical session lasts 4–30 minutes and can burn more calories than steady-state cardio in less time. Tabata, the most popular HIIT format, uses 20 seconds of all-out effort followed by 10 seconds of rest, repeated 8 times for a total of 4 minutes. It was developed by Japanese scientist Dr. Izumi Tabata and is proven to improve both aerobic and anaerobic fitness.
How to Do a Tabata Workout
Warm up for 5 minutes with light movement — jumping jacks, arm circles, or a brisk walk.
Go all-out for 20 seconds. Pick any exercise: burpees, squats, push-ups, mountain climbers.
Rest for 10 seconds. Catch your breath — you'll need it.
Repeat for 8 rounds. That's 4 minutes of work. You're done.
Press Start and we'll count for you.
Frequently Asked Questions
What is a Tabata timer?
A Tabata timer counts 20-second work intervals and 10-second rest intervals for 8 rounds. The format was developed by Dr. Izumi Tabata and is one of the most popular HIIT protocols.
How long is a HIIT workout?
A standard Tabata round takes 4 minutes. Most HIIT workouts range from 4 to 30 minutes depending on the number of exercises and rest periods.
Do I need equipment for HIIT?
No. Bodyweight exercises like burpees, jumping jacks, and mountain climbers work perfectly. Add dumbbells or resistance bands if you have them, but they're not required.
Is HIIT good for beginners?
Yes, but start at your own pace. 'All-out effort' is relative to your fitness level. Rest longer between rounds if you need to, and build up over time.
Can I use this timer on my phone?
Yes. JustHIIT It works in any mobile browser and can be installed as a PWA for an app-like experience. It also works offline once installed.