Max heart rate
176bpm
Tanaka
220 − age
175bpm
classic
Zone 2
106–124bpm
aerobic base
Vigorous from
136bpm
about 77% of max
Show the math
Max HR = 208 − 0.7 × 45 = 176 bpm
Heart rate zones at 45
| Zone | BPM | % of max | Feels like |
|---|---|---|---|
| Zone 1 · Recovery | 88–106 | 50–60% | Easy, conversational |
| Zone 2 · Aerobic base | 106–124 | 60–70% | Steady, can still talk |
| Zone 3 · Tempo | 124–141 | 70–80% | Comfortably hard |
| Zone 4 · Threshold | 141–159 | 80–90% | Hard, short phrases |
| Zone 5 · Max effort | 159–176 | 90–100% | All-out, seconds to minutes |
Karvonen zones by resting heart rate
| Resting HR | Zone 1 | Zone 2 | Zone 3 | Zone 4 |
|---|---|---|---|---|
| Resting 55 | 116–128 | 128–140 | 140–152 | 152–164 |
| Resting 65 | 121–132 | 132–143 | 143–154 | 154–165 |
| Resting 75 | 126–136 | 136–146 | 146–156 | 156–166 |
Karvonen: resting + (max − resting) × intensity. More personal if you know your resting rate.
How to use it
- Enter your numbers. Switch between US and metric units at any time.
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These are estimates, not a diagnosis. A clinician can account for your health history and medicines.
Other ages
Common questions
What is a good heart rate zone for a 45-year-old?
Zone 2, about 106 to 124 bpm, builds aerobic base. Moderate exercise sits around 113 to 134 bpm.
What is the max heart rate at 45?
About 176 bpm by the Tanaka formula, or 175 by 220 minus age. Individual max can differ by 10 or more beats.