Target Heart Rate Calculator

1. Target heart rate calculation
2. Max Heart Rate Table
3. What is a normal heart rate (pulse)?
4. Key target zones for exercise
5. Caution in using predictions for individuals

    Target heart rate calculation

When you work out, don't you wonder if you are doing too little or too much exercise? One way to tell is to compare your heart rate during exercise with your estimated target heart rate. The former you can learn from any suitable heart rate measurement device while the latter can be estimated using our free target heart rate calculator.

There are currently two methods for calculating your target heart rate (target HR) during exercise - one is the Percentage Method in which the target rate is calculated based on your maximum heart rate (table). So, the formula is simply HR_target = HR_max x Target (%). For example, if your exercise level target is 80% and your maximum heart rate is 200, you get a target HR of 200 x 0.80 = 160 beats per minute. Using our target HR calculator instead of the table you can get accurate results for any age, not just the tabulated ones.

The other approach is the Karvonen Method^[4], which uses your resting heart rate as well. In the Karvonen method the thresholds are calculated as a percentage of the difference between resting HR and max HR (termed heart rate reserve) and tends to yield somewhat higher rates than the percentage method, in general. The lower bound is (HR_max - HR_rest) x 0.5 + HR_rest, the upper bound is (HR_max - HR_rest) x 0.85 + HR_rest. Since this method came from a study with a very small sample size (6 persons) and we are unsure about its representativeness, we are only offering the percentage method in this target heart rate calculator.

Both of these methods, however, rely on the accuracy of the max. heart rate formula used, and this is where many get it wrong.

    Estimating maximum heart rate

The maximum heart rate in beats per minute (bpm) can be predicted simply by your age, regardless of gender and physical activity status using formulas obtained on the basis of observational research.

    Old max heart rate formula

For the longest time the maximum heart rate was predicted from the age using the formula 220 - Age (y), so a 20 year old would have a max HR of 200 beats per minute. It is convenient and easy to calculate, but it is not very accurate, as shown by later studies^{[1, 2]}. Unfortunately, as of early 2018 it is still used in a lot of calculators and cited in literature.

    New max heart rate formula

Tanaka & Gellish performed in 2001 and 2007 studies that demonstrated the necessity to revise this old and empirically untested formula. Tanaka produced the formula HR_max = 208 - 0.7 x Age (y) while the study by Gellish et al., which included much more subjects and followed them across a longer time span (they study was a retrospective analysis of maximal graded exercise test (GXT) results for members participating in a university-based health-assessment/fitness center), resulted in a regression with the following formula:

HR_max = 206.9 - 0.67 x Age (y)

Since this is the study with the largest sample size and possibly best predictive value, this is also the formula used in our heart rate calculator. Below you can see a comparison between the old formula (220-Age) and the two newer formulas.

* the graph is not zero-based and may appear to exaggerate the differences

As evident from the chart, the old formula overpredicts the maximum heart rate by a small margin in younger adults, while it underpredicts it significantly for older people. The three formulas agree only about the average 40-year old person. The difference between the Tanaka formula and the Gellish formula is minimal at all ages.

Max HR in higher body-fat percentage persons

If your body fat is higher than 30% of your weight (you can use our body fat calculator to estimate that), then a modification of the above formulas is recommended^[3]. The formula in this case is 200 - 0.5 x Age (y).

As visible, people with over 30% body fat percentage have lower maximal heart rate in under forty while having a higher one later on in life. Our calculator has a simple checkbox you can select in order for the equation to be adjusted accordingly.

    Max Heart Rate Table

This table is based on the study by Gellish et al., discussed above.

Maximum Heart Rate & Target HR Table

Age	Maximum Heart Rate	Target HR Zone (50-85%)
20 years	194 beats per minute	97 - 164 bpm
25 years	190 beats per minute	95 - 162 bpm
30 years	187 beats per minute	93 - 159 bpm
35 years	183 beats per minute	92 - 156 bpm
40 years	180 beats per minute	90 - 153 bpm
45 years	177 beats per minute	88 - 150 bpm
50 years	173 beats per minute	87 - 147 bpm
55 years	170 beats per minute	85 - 145 bpm
60 years	167 beats per minute	83 - 142 bpm
65 years	163 beats per minute	82 - 139 bpm
70 years	160 beats per minute	80 - 136 bpm
75 years	157 beats per minute	78 - 133 bpm
80 years	153 beats per minute	77 - 130 bpm

The results are rounded to the nearest whole number.

    What is a normal heart rate (pulse)?

Your (normal) resting heart rate is when your heart is pumping the lowest amount of blood you need for your metabolism for function. If you’re sitting or lying, calm and relaxed, and you are not currently ill, your heart rate should be between 60 and 100 beats per minute ^[5].

You can measure it by taking your pulse with your fingers (do not use your thumb, which has its own pulse) at the carotid artery (on the side of your neck, just below the chin) for exactly 15 seconds, then multiplying it by 4.

If it happens that your heart rate is lower than 60, it doesn’t necessarily mean you have a medical problem, as there can be a number of normal reasons for that. For example, it could be due to taking a drug such as a beta blocker. A lower rate is common for athletes or people who get a lot of physical activity, because their heart muscle is in better condition and doesn’t need to work as hard to pump the same volume of blood. Moderate physical activity usually has little to no effect. During exercise, your target heart rate should always be higher than your normal heart rate.

    Key target zones for exercise

This table is a rough guideline for the intensity of workout expressed in % of max heart rate. You can use it to guide what you input in the "Target exercise level" field of the calculator.

Key target heart rate zones

Zone	Effort	Effect & Purpose
50-60%	Very light exercise	Improves heart health. Improvement to blood pressure, muscle mass, lowers cholesterol & risk of degenerative diseases. High safety.
61-70%	Light effort	High fat burn, muscle gains. Trains your body to burn fat and increases the number of mitochondria in the muscle. Good for weight loss.
71-80%	Moderate exercise	Aerobic effort. Improves vital capacity, respiratory rate, increases size & strength of the heart and cardiac output.
81-90%	Hard exercise	Maximum fat burn, but only if you are fit enough. Improves VO 2 and you become less susceptible to sore muscles.
91-100%	Extreme effort	Athlete level, sustained for short periods of time (interval workouts). Develops fast-twitch muscles. High risk of over training and injuries!

These exercise intensity levels and their related heart rate zones are averages and one should never blindly follow them. When exercising, always consider the advice of coaches and medical specialists, and also what your body is telling you to avoid unnecessary harm and health issues.

    Caution in using predictions for individuals

This calculator uses a prediction formula based on statistical analysis of a sample of the population, which means there is an inherent plus/minus error so it should be used with caution when trying to determine a specific person's maximum heart rate. For example, within normal variation limits the max. HR of a 40-year-old man or woman can vary between 160 and 200 bpm in 95% of cases.