Target Heart Rate Calculator

How does this target heart rate calculator function?

This health tool can help you answer to “what is my target heart rate” and will offer some more personalized information as well. It uses the Karvonen method, explained below and takes account of your age and resting heart rate (which should be measured right after you get up) to determine the optimal heart rate and the range of the target heart rate. Please note that in general the human heart rate ranges between 60 and 100 beats per minute (bpm).

The need for such a calculator occurred when it was discovered that in order to maximize the advantages of cardiovascular activity it is recommended to exercise in the zone of target heart rate (THR) which is generally speaking at 60-80% of maximum heart rate.

The Karvonen formula

Target Heart Rate = ((max HR − resting HR) × %Intensity) + resting HR example

This is a mathematical formula designed to determine the THR training zone. The Karvonen heart rate formula is one of the most used formulas and its steps are explained below:

1. Calculating Maximum heart rate = 220 – Your age in years.

2. Calculating Heart rate reserve (HRR) = Maximum heart rate – Resting heart rate value.

3. Calculating Min. of the target heart rate for the target heart rate range = Heart rate reserve * 0.6.

4. Calculating Max. of the target heart rate for the target heart rate range = Heart rate reserve * 0.8.

5. Calculating the ideal average Target Heart Rate = (Min. of the target heart rate + Max. of the target heart rate)/2.

Please note that the ideal target heart rate calculations performed by this calculator are an estimation and that heart rates differ from one person to another so the results presented by this tool do not pretend to be 100% accurate. Please note that the min factor of 0.6 and max factor of 0.8 are subjective.

Example calculation explained:

Let’s take for instance the case of a 30 years old person with a resting heart rate measured right after waking up of 65 bmp.

Step 1: Calculating Maximum heart rate = 220 – 30 = 190 bpm.

Step 2: Calculating Heart rate reserve (HRR) = 190 – 65 = 125 bpm.

Step 3: Calculating Min. of the target heart rate for the target heart rate range = 125 * 0.6 = 75 bpm.

Step 4: Calculating Max. of the target heart rate for the target heart rate range = 125 * 0.8 = 100 bpm.

Step 5: Calculating ideal average Target Heart Rate = (75 + 100)/2 = 87.5 bpm.

Target heart rate chart including the zones

Table source: American Heart Association

References

1) Kolata G. (2001) Maximum Heart Rate Theory Is Challenged. New York Times.

2) Tanaka H, Monahan KD, Seals DR. (2001) Age-predicted maximal heart rate revisited. J Am Coll Cardiol.  37(1):153-6.