This fat burning zone calculator gives you the heart rate zone in which you need to train in order to lose weight and burn fat. There is more information about the calculator and how it computes the training zone for weight loss below the form.

Resting heart rate :*

How does this fat burning zone calculator work?

This health tool determines the two cardiac heart zones in which fat burning is most predominant when exercising. The heart beat values in beat per minute are calculated by taking into account the maximum heart rate (MHR) and the resting heart rate (RHR).

The fat burning zone calculator provides six results, by using beat per minute ranges in three different methods. The first method uses the percentage of the max heart rate, the second one uses the Karvonen method with % from the heart rate reserve HRR (which is MHR – RHR) plus the resting heart rate. The third method is the Zoladz calculation with 10 bpm difference in intervals created by subtracting a specific number of beats per minute from the max rate.

Zone Description Intensity % of MHR Karvonen (% of HRR + RHR) Zoladz (- BPM)
3 Aerobic Intense 70 - 80 70 - 80 MHR - 35
2 Endurance Moderate 60 - 70 60 - 70 MHR - 45

While the heart rates can be a good indicator of fitness, training using heart zones is a highly controversial method nowadays, some people considering its promises a myth while others abiding by them during all their training.

Fat burning zone

This cardio zone is defined as the zone between 60 - 75%, however, when using the classical model of 5 heart training zones, is extended to 80%.

On the other hand, criticism of the method implies that working at above 80% seems to burn more calories than the above mentioned. The difference seems to be in the type of work out, the difference between high intensity and low intensity and the target areas where the body takes its energy during each zone.

In the 5 zone model: i.e. VO2 max, Anaerobic, Aerobic, Endurance and Recovery, zone 2 and 3 are the ones between the 60 – 80 percentile.

Zone three or the aerobic zone for stamina is said to develop the cardiovascular system and improves respiratory function and blood gases circulation. It helps build muscle mass but also increases fat burning. This zone is used for marathon training as well.

Zone two or the endurance energy efficient zone is focused on burning fat and can be used in weight loss programs while developing basic endurance. It is a less strenuous zone in terms of muscle work and helps regenerate in between vigorous workouts in higher zones.

Example of a calculation

Taking the case of a person with a maximum heart rate of 185 bpm and resting heart rate of 60. Their heart resting reserve is 125 bpm and their fat burning zones are:

Zone Description Intensity % of MHR Karvonen (% of HRR + RHR) Zoladz (- BPM)
3 Aerobic Intense 130 - 148 148 - 160 140 - 150
2 Endurance Moderate 111 - 130 135 - 148 130 - 140


1) Karvonen J, Vuorimaa T. (1988) Heart rate and exercise intensity during sports activities. Practical application. Sports Med; 5(5):303-11.

2) Carey DG. (2009) Quantifying differences in the "fat burning" zone and the aerobic zone: implications for training. J Strength Cond Res; 23(7):2090-5

3) Nicklas BJ, Wang X, You T et al. (2009) Effect of exercise intensity on abdominal fat loss during calorie restriction in overweight and obese postmenopausal women: a randomized, controlled trial1,2,3,4 Am J Clin Nutr; 89(4): 1043–1052.

12 Feb, 2016