HIIT Interval Timer — Free Online High Intensity Training Clock

8 rounds
Ready
00:40
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What Is HIIT Training?

High-Intensity Interval Training (HIIT) alternates between periods of intense effort and rest or low-intensity recovery. Unlike steady-state cardio, HIIT keeps your heart rate elevated and burns more calories in less time.

Using This HIIT Timer

  • The default preset is 40 seconds work / 20 seconds rest / 8 rounds.
  • Use the Settings gear to customize work time, rest time, and number of rounds for your specific workout.
  • The background color shifts between warm orange for work and teal for rest so you can see your current phase at a glance.
  • Audio beeps signal the start of each new round.

HIIT vs. Tabata

Tabata is a specific HIIT protocol (20s/10s/8 rounds). General HIIT is more flexible — work intervals typically range from 20 to 60 seconds, and rest periods vary based on fitness level and workout goal. Use our Tabata Timer if you want the strict 20/10/8 format.