How to Calculate Max Heart Rate
Max heart rate is the highest number of beats per minute (bpm) that your heart can safely achieve during maximal physical exertion. It is a cornerstone metric for designing aerobic and interval training sessions, pacing races, and preventing overtraining. Because individual differences exist, there are multiple validated ways to arrive at that peak number.
The most common approximation is the classic formula: subtract your age from 220. It was developed from a wide range of study participants and provides a quick starting point. For a slightly more accurate prediction across a broader age span, the Tanaka formula subtracts 0.7 times your age from 208, which accounts for the gradual decline in cardiovascular capacity with aging.
Once you know your max heart rate, you can multiply it by the desired intensity percentage to calculate training zones. For example, a 35-year-old athlete using the classic formula has a max heart rate of 185 bpm (220 − 35). At an 80% intensity, target heart rate becomes 148 bpm for steady aerobic work. The same athlete's Tanaka max is 183.5 bpm, yielding a target of 147 bpm at 80% intensity.
Regularly updating your age-based max heart rate and checking it against your perceived exertion improves the safety and effectiveness of your workouts. Combine this metric with resting heart rate and perceived effort for a fuller picture of your cardiovascular fitness.