Calculate personalized heart rate training zones using age-estimated or tested maximum heart rate and Karvonen reserve method.
Max Heart Rate Formula:
Heart rate is a measure of the number of contractions the heart makes per minute. It is measured in beats per minute (bpm). To effectively use this target heart rate calculator, it is important to understand the concepts of resting heart rate, maximum heart rate, and heart rate reserve.
Maximum heart rate is a measure of the highest number of beats per minute the heart reaches during intense exercise. It is most accurately measured through a cardiac stress test, which typically involves exercising on a treadmill while being monitored by an electrocardiogram (ECG). As the subject walks/runs on the treadmill, the intensity is periodically increased until certain changes in heart function indicating maximum heart rate are detected. The theoretical maximum human heart rate is 300 bpm.
More commonly, maximum heart rate is estimated using various formulas. It is worth noting that maximum heart rate formulas have been criticized as inaccurate as they output generalized population averages and estimates can vary significantly from an individual's maximum heart rate. Maximum heart rate is largely correlated with age, and most formulas are primarily based on this.
Haskell & Fox Formula (1971):
Tanaka, Monahan, & Seals Formula (2001):
Nes, Janszky, Wisloff, Stoylen, Karlsen Formula (2013):
Resting heart rate is a measure of a person's heart rate at rest, where rest is defined as when a person is awake in a neutral environment that is neither too hot nor cold, and the person is not subject to stress or surprise. It can be measured using a variety of devices or just by counting your pulse over a minute.
A typical resting heart rate (RHR) for an adult ranges between 50-90 bpm. Some sources state this range as 60-100 bpm, but this range is slightly dated. A resting heart rate above the upper range is referred to as tachycardia while one below the lower range is referred to as bradycardia. A RHR in the 50-60 range in some cases may be considered bradycardia, but very fit athletes often have RHRs in this range, and sometimes even below.
A person's heart rate reserve (HRreserve) is the difference between their maximum heart rate (MHR) and their resting heart rate (RHR):
For example, given a person has a maximum heart rate of 180 bpm and a resting heart rate of 68, their heart rate reserve is:
HRreserve = 180 − 68 = 112 bpm
There are various methods used to measure intensity of exercise in relation to heart rate. Generally, the more intense the exercise, the higher the heart rate. Maintaining a heart rate within a certain range, referred to as the target heart rate (or training heart rate range), has been found to be beneficial for exercise.
A person's target heart rate zone is typically broken up into five zones which impart different benefits:
| Zone | Intensity Range | Training Benefit |
|---|---|---|
| Zone 1 (Very Light) | 50 – 60% | Warm up, cool down, active recovery, easy training days |
| Zone 2 (Light) | 60 – 70% | Fat burning, aerobic endurance, long steady sessions |
| Zone 3 (Moderate) | 70 – 80% | Building speed, strength endurance, improved cardio capacity |
| Zone 4 (Hard) | 80 – 90% | Lactate threshold training, sustained high output capacity |
| Zone 5 (Max) | 90 – 100% | Peak VO2, anaerobic capacity, short maximal intervals |
This method for calculating target heart rate zones is one of the most straightforward and widely used methods and is based only on maximum heart rate computed using age. This is the method used when only an age and no resting heart rate is entered.
The Karvonen method calculates target heart rate zone using heart rate reserve (HRreserve), which factors in resting heart rate (RHR) on top of maximum heart rate (MHR) rather than just MHR. This is the default method used when a resting heart rate and age are plugged in.
Rating of perceived exertion (RPE) is an indicator of exercise intensity that allows a person to subjectively rate their level of exertion while exercising. This is beneficial because it doesn't require measurement of physiological parameters such as heart rate, lactate levels, etc.
The Borg scale is the original RPE scale and is a scale ranging from 6-20, where 6 indicates no exertion and 20 indicates maximum exertion. The scale is designed such that it corresponds closely to heart rate. Each value multiplied by 10 approximates heart rate at that given exertion level.
| RPE Value | Perceived Exertion |
|---|---|
| 6 | No exertion at all |
| 7 | Extremely light |
| 9 | Very light |
| 11 | Light |
| 12 | Moderate |
| 13 | Somewhat hard |
| 15 | Hard |
| 17 | Very hard |
| 19 | Extremely hard |
| 20 | Maximal exertion |
The Borg CR10 scale is the modified version of the Borg scale on a scale of 0-10. 0 represents no exertion at all while 10 represents the strongest exertion an individual has experienced.
| RPE Value | Perceived Exertion |
|---|---|
| 0 | No exertion |
| 0.5 | Noticeable |
| 1 | Very light |
| 2 | Light |
| 3 | Moderate |
| 4 | Somewhat difficult |
| 5 | Difficult |
| 7 | Very difficult |
| 9 | Almost maximal |
| 10 | Maximal |
Maximum heart rate formulas provide population averages and individual results can vary significantly. Elite athletes of the same age can have maximum heart rates differing by 60 bpm or more. For highest accuracy, use a directly measured maximum heart rate from a graded exercise test.
Always warm up gradually before entering higher intensity zones. If you experience chest pain, dizziness, severe shortness of breath or irregular heartbeat during exercise, stop immediately and consult a healthcare provider. This calculator is for educational and fitness planning purposes only and is not a substitute for professional medical advice.