HR Max Calculator
Maximum heart rate
180 bpm
Heart Rate Zone Calculator
Target zone, lower bound
115 bpm
Target zone, upper bound
137 bpm
Zone 2 lower bound
108 bpm
Zone 2 upper bound
126 bpm
Equation used
Tanaka (208 - 0.7 x age)
Zone method
Percentage of maximum heart rate
Published standard error of the equation
10.0 bpm
Worked out from Fox SM, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res 1971;3:404-432. and 6 other sources.
Tanaka (208 - 0.7 x age) has a published standard error of about 10 bpm, so your true maximum could plausibly be 160 to 200 bpm.
Age-predicted maximum heart rate carries a standard error of roughly 7 to 12 beats per minute, so an individual can sit 20 bpm either side of the estimate. Beta blockers, other rate-limiting drugs, pacemakers, atrial fibrillation and heat or altitude all change these numbers. Anyone with a cardiac condition or symptoms on exertion should have their zones set by a clinician, not by an equation.
How this is worked out
3 steps
- Tanaka (208 - 0.7 x age): HRmax = 208 - 0.7 x 40 = 180 bpm.
- Percentage of maximum: target = intensity x HRmax.
- Target zone 64-76%: 115.2 to 136.8 bpm.
Training zonestable
| zone | label | lowPercent | highPercent | lowBpm | highBpm |
|---|---|---|---|---|---|
| 1 | Very light - recovery | 50 | 60 | 90 | 108 |
| 2 | Light - aerobic base | 60 | 70 | 108 | 126 |
| 3 | Moderate - aerobic | 70 | 80 | 126 | 144 |
| 4 | Hard - threshold | 80 | 90 | 144 | 162 |
| 5 | Maximum - anaerobic | 90 | 100 | 162 | 180 |
Results are general information, not financial, tax, legal, medical or engineering advice.