Karvonen Heart Rate Calculator
Heart rate zones using your resting heart rate.
Max HR
190
Resting
60
HR reserve
130
| Zone | Intensity | BPM range |
|---|---|---|
| Z1 Recovery | 50-60% HRR | 125 - 138 |
| Z2 Endurance | 60-70% HRR | 138 - 151 |
| Z3 Tempo | 70-80% HRR | 151 - 164 |
| Z4 Threshold | 80-90% HRR | 164 - 177 |
| Z5 VO2 max | 90-100% HRR | 177 - 190 |
Karvonen formula: target HR = resting HR + (max HR - resting HR) x intensity. Max HR uses the simple 220 minus age estimate. Pick a quiet morning to measure resting heart rate for the cleanest number.
About
The simple formula (220 minus age) ignores that fit people have lower resting rates. Karvonen uses heart rate reserve (max minus resting) for more accurate zones. Better for endurance training.
How to use
- Enter your age and resting heart rate.
- See zones 1 through 5 (recovery to max effort).
FAQ
How do I find my resting heart rate?+
Take it in bed before getting up, three days in a row, and average. Or use a fitness tracker. Typical range is 60-80 bpm. Trained athletes are often 40-60.
Why use Karvonen over standard zones?+
Standard zones (60% max, 70% max) ignore your fitness level. Karvonen scales to your actual heart rate range. A 50-year-old with a 50 bpm resting rate has very different zones than someone with 80 bpm.