Karvonen Heart Rate Calculator
Calculate target heart rate zones using the Karvonen formula, which accounts for resting heart rate for more personalized training zones than age-based methods alone.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| Karvonen Heart Rate Calculator | — | THR = ((HRmax-HRrest) × %Intensity) + HRrest | beats per minute |
Step-by-Step Examples
Age 35, resting HR 60bpm, targeting 70% intensity.
- HRmax = 220-35 = 185 bpm
- HRR = 185-60 = 125 bpm
- THR = (125×0.70)+60 = 87.5+60 = 147.5 ≈ 148 bpm
Age 28, resting HR 55bpm, targeting 50% intensity.
- HRmax = 220-28 = 192 bpm
- HRR = 192-55 = 137 bpm
- THR = (137×0.50)+55 = 68.5+55 = 123.5 ≈ 124 bpm
Age 40, resting HR 58bpm, targeting 85% intensity.
- HRmax = 180 bpm, HRR = 122 bpm
- THR = (122×0.85)+58 = 103.7+58 = 161.7 ≈ 162 bpm
Real-World Applications
Common Mistakes to Avoid
Measure your actual resting heart rate (lowest HR upon waking, before getting up) for accuracy — don't assume a textbook average of 60-70 bpm.
Karvonen (Heart Rate Reserve method) is more personalized than simply taking a percentage of HRmax alone, since it accounts for fitness level via resting HR.
Beta-blockers and other heart medications can significantly lower both resting and maximum heart rate, making formula-based estimates inaccurate for some individuals.