How to use
- Enter your age and choose a formula. Tanaka is the default; 220 − age is the traditional rule.
- Know your real maximum from an exercise test? Enter it to replace the estimate.
- Choose % of max or heart rate reserve. The reserve (Karvonen) method also needs your resting heart rate.
- Read your maximum, your five zones and the AHA moderate and vigorous ranges.
How the zones are calculated
Maximum heart rate (Tanaka) = 208 − 0.7 × age
Maximum heart rate (traditional) = 220 − age
% of max: target = maximum × %
Karvonen: target = resting + % × (maximum − resting)
Maximum minus resting is your heart rate reserve. Because it builds in your resting heart rate, it raises every zone, the easy ones most.
| Zone | Share of max or reserve | Feels like |
|---|---|---|
| 1 | 50–60% | Very easy, relaxed breathing |
| 2 | 60–70% | Comfortable, you can still chat |
| 3 | 70–80% | Talking gets harder |
| 4 | 80–90% | Fast, breathing forcefully |
| 5 | 90–100% | All-out, short bursts only |
These five bands are a convention used by fitness watches such as Polar and Garmin. The American Heart Association describes 50–70% of your maximum as moderate exercise and 70–85% as vigorous.
Examples
- Age 35, Tanaka: 208 − 0.7 × 35 = 183.5, about 184 bpm. Zone 2 is 110–128 bpm; the AHA moderate range is 92–128 bpm.
- Age 40, resting 60 bpm, Karvonen: maximum 180, reserve 120. Zone 2 is 60 + 0.6 × 120 to 60 + 0.7 × 120 = 132–144 bpm, against 108–126 bpm by % of max.
- Age 60: Tanaka gives 166 bpm, the traditional rule 160 bpm.
Maximum heart rate by age
| Age | 220 − age | Tanaka | Zone 2 (Tanaka) |
|---|---|---|---|
| 20 | 200 | 194 | 116–136 |
| 30 | 190 | 187 | 112–131 |
| 40 | 180 | 180 | 108–126 |
| 50 | 170 | 173 | 104–121 |
| 60 | 160 | 166 | 100–116 |
| 70 | 150 | 159 | 95–111 |
All values are beats per minute, rounded to the nearest beat.
How accurate are age formulas?
Tanaka’s 2001 equation pooled 351 studies with 18,712 people, then was confirmed in a lab study of 514 adults. It found that 220 − age underestimates the maximum in older adults.
The 220 − age rule was never derived from original research. A 2002 commentary traced it to a rough line fitted to data compiled in 1971.
Any age formula can be off by about 7 to 11 bpm for an individual. A supervised exercise test gives a real maximum.
These figures are estimates for healthy adults. Some medicines, such as beta-blockers, lower your heart rate; ask your doctor which range to use. Training for a race? Turn your zones into a target speed with the running pace calculator.