This heart rate zone calculator determines the 5 heart training zones for your fitness activity whether you want to lose weight, build strength or endurance. There is more information about each of the heart rate ranges, how to calculate it and its benefits below the form.

Resting heart rate :*

How does this heart rate zone calculator work?

This health tool estimates the ranges of heart beats per minute for each of the 5 training zones. There are three methods of calculation available, each with separate percentages that take account for the Maximum Heart Rate (MHR) and the Heart Resting Rate (HRR).

These are also the only two variables you need to input in the heart rate zone calculator. In case you don’t know your max heart rate, you can compute it with this tool based on your age. There are several formulas available there such as that of Tanaka, Monahan, & Seals or Haskell and Fox.

The HRR is easy to calculate, when at rest and lying down after no period of exertion. You are advised to measure it after 20 minutes since you have lied down. For most people this varies between 60 and 80 beats per minute.

An exercised heart is more efficient as a pump and therefore, in people who frequently exercise, the normal resting heart rate tends to be lower.

The following table presents the available heart zones and after it, each of the calculation methods is explained.

Zone Description Intensity % of MHR Karvonen (% of HRR + RHR) Zoladz (- BPM)
5 VO2 max Maximal 90 - 100 90 - 100 (MHR - 25) - (MHR - 15)
4 Anaerobic Very Intense 80 - 90 80 - 90 (MHR - 35) - (MHR - 25)
3 Aerobic Intense 70 - 80 70 - 80 (MHR - 45) - (MHR - 35)
2 Endurance Moderate 60 - 70 60 - 70 (MHR - 55) - (MHR - 45)
1 Recovery Light 50 - 60 50 - 60 (MHR - 65) - (MHR - 55)

The first three columns are aimed at describing the type of zone while the fourth column exemplifies the simplest method of determining the training range for each zone, as a percentage from the maximum heart rate.

The fifth column exemplifies the percentages in the Karvonen method which is slightly more complicated because it involves another notion, the reserve heart rate (RHR) which is the difference between MHR and HRR. The % are applied to the reserve heart rate which is then added to the resting rate.

For example, in the case of a subject with a resting rate of 60 bpm and a maximum heart rate of 185 bpm:

The reserve heart rate is 185 – 60 = 125.

The percentages corresponding to zone 5 are 90% and 100%.

This means 113 – 125 bpm.

By adding the resting rate to the above values, we obtain: 173 – 185 bpm.

The sixth column presents the Zoladz method which has established a number of bpm units that need to be extracted from the MHR, depending on the training zone. The other end of the range is 10 bpm smaller than the higher end in all zones. Taking the same example as above, at a MHR of 185, the Zoladz zone 5 interval would be 160 – 170 bpm.

Although these calculations are accurate enough for individual estimations, there are several other personal and environmental factors that influence heart beats per minute and heart condition such as:

Dehydration – increase heart rate by almost 8% and there are also normal variation from day to day;

Altitude increases heart rate between 10 – 20%;

Humid and hot environment increases heart rate by 10 bpm/minute.

Heart training zones

Each training zone comes with different physiological effects and is used for a different fitness aim, these are either estimated through methods like the three presented above or through a cardio assessment.

A training zone is useful in structuring training in order to meet certain goals but at the same time in order to ensure the heart is not under or over worked during prolonged periods of effort of different intensities or that risk of other injuries doesn’t occur.

The following table correlates the ability of each zone to meet weight loss, endurance and strength goals in order to direct you to which of the zones you need to focus on.

Zone Weight loss Endurance Strength/Speed
5 L L H
4 L M H
3 M H M
2 H H L
1 H M L

Where: L - Low effect | M - Medium effect | H - High effect.

Zone 5 – The red line zone, also known as VO2 max or anaerobic training, usually at 90 – 100%, represents the maximum intensity achievable and helps develop speed and strength. This zone is reserved for very fit persons and athletes. During it, lactic acid develops because of the oxygen debt to the muscles.

Zone 4 – The anaerobic zone, also known as the lactate threshold zone or tempo run, usually at 80 – 90%, is aimed at working out the lactic acid system and developing endurance and speed. This is the zone in which the main source of energy is extracted from the glycogen stored in the muscles rather than from fat. Discovering the anaerobic threshold can increase the body’s ability to deal with lactic acid for longer periods of time. This zone is indicated for persons in good shape with healthy heart rates and often used in training for races.

Zone 3 – the aerobic zone for stamina or the target heart rate zone, usually at 70 – 80%, develops the cardiovascular system and improves the body’s ability to transport respiratory gases, i.e. O2 and CO2, in and out of the body. This zone allows a better development of muscular mass but also increases fat burning. This is the zone used for marathon training, somewhat recognized as a golden zone for most fitness goals.

Zone 2 – the endurance energy efficient zone, usually at 60 – 70%, develops basic endurance and is also recognized as easy recovery running. It is a zone focused on burning fat and is not so strenuous on the muscles, thus allowing them to regenerate, whatever might have been used in higher zone trainings.

Zone 1 – the recovery zone, with the lowest intensity at 50 – 60% capacity, easy training that still has an impact on physical condition. This zone uses body fat as energy source and is said to be the first choice for beginners or during prolonged recovery periods. This zone is also the one with the best weight loss results.


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

2) Karvonen J, Kentala E, Mustala O. (1957) The effects of training on heart rate; a longitudinal study. Ann Med Exp Biol Fenn; 35(3):307-15.

3) Zoladz JA, Majerczak J, Duda K, Chtopicki S. (2010) Endurance training increases exercise-induced prostacyclin release in young, healthy men--relationship with VO2max. Pharmacol Rep; 62(3):494-502.

4) Miller WC, Wallace JP, Eggert KE. (1993) Predicting max HR and the HR-VO2 relationship for exercise prescription in obesity. Med Sci Sports Exerc; 25(9):1077-81.

5) Uth N, Sorensen H, Overgaard K, Pedersen PK. (2004) Estimation of VO2max from the ratio between HRmax and HRrest--the Heart Rate Ratio Method. Eur J Appl Physiol. 2004 Jan; 91(1):111-5.

09 Feb, 2016