Three published equations predict maximum heart rate from age alone. They agree at one age and drift apart at the others. Here they are side by side for ages 20 to 80, computed with the same code as the heart rate zone calculator.
The chart
| Age | Tanaka: 208 − 0.7 × age | 220 − age | Gulati (women): 206 − 0.88 × age |
|---|---|---|---|
| 20 | 194 bpm | 200 bpm | 188 bpm |
| 25 | 191 bpm | 195 bpm | 184 bpm |
| 30 | 187 bpm | 190 bpm | 180 bpm |
| 35 | 184 bpm | 185 bpm | 175 bpm |
| 40 | 180 bpm | 180 bpm | 171 bpm |
| 45 | 177 bpm | 175 bpm | 166 bpm |
| 50 | 173 bpm | 170 bpm | 162 bpm |
| 55 | 170 bpm | 165 bpm | 158 bpm |
| 60 | 166 bpm | 160 bpm | 153 bpm |
| 65 | 163 bpm | 155 bpm | 149 bpm |
| 70 | 159 bpm | 150 bpm | 144 bpm |
| 75 | 156 bpm | 145 bpm | 140 bpm |
| 80 | 152 bpm | 140 bpm | 136 bpm |
What the numbers show
- 220 − age is the oldest rule. It falls by a full beat per year of age, so it is the highest of the three at 20 (200 bpm) and 12 beats below Tanaka at 80 (140 against 152 bpm).
- Tanaka (208 − 0.7 × age) falls more slowly, 0.7 beats per year. It was fitted in 2001 on a meta-analysis of 351 studies with 18,712 people and checked in a lab study of 514 adults. It crosses 220 − age at exactly 40, where both give 180 bpm. Below 40 it gives lower numbers than 220 − age, above 40 higher ones.
- Gulati (206 − 0.88 × age) comes from maximal exercise tests of 5,437 women (Gulati and colleagues, 2010). It sits below both other lines at every age in the chart: 188 bpm at 20, 171 at 40 and 136 at 80. The authors concluded that the traditional, male-based calculation overestimates max heart rate for age in women.
Zone 2 by age
Many training plans talk about "Zone 2". On this site it is the band from 60 to 70% of max heart rate. With Tanaka's equation:
| Age | Max (Tanaka) | Zone 2: 60–70% of max |
|---|---|---|
| 20 | 194 bpm | 116–136 bpm |
| 30 | 187 bpm | 112–131 bpm |
| 40 | 180 bpm | 108–126 bpm |
| 50 | 173 bpm | 104–121 bpm |
| 60 | 166 bpm | 100–116 bpm |
| 70 | 159 bpm | 95–111 bpm |
With a resting heart rate, the heart rate zone calculator switches to heart-rate reserve (Karvonen), and every zone moves up. For age 40 and a resting rate of 60, Zone 2 becomes 132–144 bpm instead of 108–126.
How far off can a prediction be?
All three equations describe averages. Any one person's measured maximum can sit well above or below the line for their age, by more than the gaps between the equations. That is why the calculator has an "I know mine" option for a value measured in a supervised test. The equations also aren't made for people on medication that changes heart rate, such as beta-blockers, or for people with heart conditions.
This page is arithmetic on published equations, not medical advice. See the Health disclaimer.