Fat Burning Zone Calculator
Find your optimal heart rate zones for fat burning and cardio fitness.
Heart Rate Zones (Max HR: 190 bpm)
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What is a Fat Burning Zone Calculator?
The fat burning zone refers to the range of exercise intensity — measured as a percentage of maximum heart rate — at which your body uses the highest proportion of fat as its primary fuel source. This zone is typically 60–70% of your maximum heart rate.
At lower intensities, fat provides a greater percentage of the energy used, but total calorie burn is lower. At higher intensities, carbohydrates become the dominant fuel, but total calorie burn is much higher. For overall fat loss, total calorie deficit matters most — but the fat burning zone is useful for long, sustainable cardio sessions.
Your maximum heart rate is estimated as 220 minus your age (Haskell & Fox formula). This is an average; individual maximum heart rates can vary by ±10–20 bpm. A stress test with a cardiologist provides the most accurate measurement.
How to Use the Fat Burning Zone Calculator
Find your personalized heart rate zones for fat burning and cardio training.
- 1
Enter your age
Your age is used to estimate your maximum heart rate using the 220 minus age formula.
- 2
Enter your resting heart rate (optional)
For more accurate zones using the Karvonen method, enter your resting heart rate (measured first thing in the morning).
- 3
View your heart rate zones
The calculator displays your target heart rate for the fat burning zone (60–70% max HR), cardio zone (70–85%), and peak zone (85–95%).
- 4
Use the zones during exercise
Wear a heart rate monitor during cardio and aim to keep your heart rate within the target zone for your goal.
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