What is an Interval Timer?
An interval timer is a timer optimized for interval training that alternates between exercise and rest periods. It supports various workout protocols including Tabata (20s work/10s rest/8 rounds) and HIIT (High-Intensity Interval Training).
Freely set work time, rest time, and number of rounds, or use built-in Tabata and HIIT presets. No installation needed - use it directly in your browser.
Key Features
Tabata Preset
One-click setup for the authentic Tabata protocol: 20s work / 10s rest / 8 rounds.
Custom Settings
Freely set work time (5s-10min), rest time (5s-5min), and rounds (1-50) for your workout.
Auto Switching
Automatically cycles work → rest → work with current round and remaining time displayed prominently.
5 Alarm Sounds
Choose from 5 alarm sounds for work/rest transitions. Vibration alerts also supported.
Screen Wake Lock
Prevents the screen from turning off during workouts. Use with confidence on smartphones.
How to Use
- Step 1: Preset or Custom — Select Tabata (20s/10s/8 rounds) or HIIT preset, or set custom times and rounds.
- Step 2: Configure Alarm — Choose alarm sound for work/rest transitions, set volume and vibration.
- Step 3: Start Workout — Press Start for automatic work → rest → work cycling.
- Step 4: Complete — Completion alarm sounds when all rounds are done. Check your total workout time.
Use Cases
Tabata Workouts
Optimized for authentic Tabata: 20 seconds all-out exercise + 10 seconds rest for 8 sets.
HIIT Training
Set your own high-intensity interval training program with custom work/rest intervals.
CrossFit & Circuits
Use for CrossFit WODs, circuit training, and various workout programs.
Running & Cardio
Interval running (sprints + jogging) to effectively improve endurance and fitness.
Frequently Asked Questions (FAQ)
What is Tabata training?
Developed by Dr. Izumi Tabata in Japan, it's a HIIT protocol of 20 seconds all-out exercise + 10 seconds rest for 8 sets (4 minutes total). It improves both aerobic and anaerobic capacity in a short time.
What's the difference between HIIT and Tabata?
Tabata is a specific type of HIIT. HIIT is the general term for high-intensity interval training with flexible work/rest times and rounds. Tabata is a fixed protocol of 20s work / 10s rest / 8 rounds.
Can I customize work/rest times and rounds?
Yes, freely set work time (5s-10min), rest time (5s-5min), and rounds (1-50). Tabata and basic HIIT presets are also available.
Can I pause during an interval?
Yes, press the pause button at any time during work or rest. Resume to continue from where you stopped.
How can I use the interval timer beyond workouts?
Study sessions (focus/rest cycles), cooking (timing each step), presentation practice, and more. Freely adjust work/rest times and rounds to fit any scenario.
Can I see the current and remaining rounds during interval?
Yes, the screen shows current/total rounds, remaining time, and work/rest status in real time.
The Science of HIIT: Why Intervals Work
The key mechanism is EPOC (Excess Post-Exercise Oxygen Consumption), commonly called the "afterburn effect." After intense intervals, your body continues burning calories at an elevated rate for 24-48 hours as it restores oxygen levels, clears lactate, and repairs muscle tissue. Studies show HIIT can burn 25-30% more calories than steady-state cardio of equal duration.
At the cellular level, HIIT triggers mitochondrial biogenesis — your muscles literally grow more mitochondria (the energy-producing organelles), increasing your aerobic capacity. Research by Dr. Martin Gibala at McMaster University demonstrated that just 3 sessions of 20-minute HIIT per week produced the same cardiovascular improvements as 5 sessions of 45-minute moderate cycling.
HIIT also improves insulin sensitivity by rapidly depleting muscle glycogen stores, forcing muscles to absorb more glucose from the bloodstream during recovery. This makes it particularly beneficial for metabolic health.
Popular Interval Protocols Compared
Tabata (20s work / 10s rest / 8 rounds = 4 min): Developed by Dr. Izumi Tabata in 1996. Performed at 170% of VO2max. Proven to improve both aerobic and anaerobic capacity simultaneously. Extremely demanding — true Tabata intensity means complete exhaustion by round 7-8.
EMOM (Every Minute On the Minute): Perform a set number of reps at the start of each minute; rest for the remainder. Self-regulating — faster reps earn more rest. Popular in CrossFit for strength-endurance work. Typical duration: 10-20 minutes.
AMRAP (As Many Rounds As Possible): Complete as many rounds of a circuit as possible within a fixed time (usually 10-20 min). Great for tracking progress over time since the workout stays constant.
Little Method (60s work / 75s rest / 8-12 rounds): Developed by researchers at McMaster University. Work at ~95% max heart rate. The longer rest allows near-complete recovery, enabling consistently high intensity. Total session: 18-27 minutes. Ideal for intermediate athletes building toward more intense protocols.
Privacy Notice
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