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FREE TOOLS

Online Tabata timer

20 seconds on, 10 seconds off, 8 rounds, with a beep at every change, free in your browser

Interval timer

Ready when you are

00:20

Keep this tab open and in front: browsers can slow down timers in background tabs. The Cero app keeps going with your screen locked, on your Apple Watch and in the Dynamic Island.

How to use it

  1. Press Start: you get 10 seconds to get ready, then 8 rounds of 20 seconds of work and 10 of rest.
  2. Listen for the beeps: three short ones before each change, a high one for work and a low one for rest.
  3. For two blocks in a row, pick Double Tabata: 16 rounds, 8 minutes.

What is a Tabata?

A Tabata is 8 rounds of 20 seconds of very hard work and 10 seconds of rest, 4 minutes in all, named after Izumi Tabata’s 1996 study on an exercise bike 1. Most classes do several Tabata blocks with a different exercise in each and a minute of rest between them. Read how long a Tabata workout is.

Exercise ideas

  • Squats or jump squats
  • Burpees
  • Mountain climbers
  • Kettlebell swings
  • Sprints on a bike or rower

Sources

  1. Tabata I, Nishimura K, Kouzaki M, et al. Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max. Med Sci Sports Exerc. 1996;28(10):1327-1330. doi.org/10.1097/00005768-199610000-00018

YOUR NEXT SESSION STARTS HERE

Bring the effort.
We’ll keep the time.

Cero is free to download for iPhone, iPad and Apple Watch.

Download Cero
Cero’s interval builder on iPhone 18 Pro, with the template picker, warm-up, work, recovery and cool-down intervals, and per-interval timing controls

Cero is a timer, not a medical device. If you’re new to hard exercise, are pregnant or have a health condition, check with your doctor first, and stop if you feel unwell.