How to use this calculator
- Enter your age.
- Add resting heart rate if known.
- Enter average workout heart rate.
- Add workout duration to estimate recovery demand.
Use this Fitness Heart Rate Calculator to estimate your workout intensity and target heart-rate zone. It compares your average exercise heart rate with estimated maximum heart rate, then shows whether your session is closer to recovery, fat-burning, cardio, or high-intensity training.
Heart-rate zones help classify workout intensity. Lower zones support recovery and endurance base. Higher zones increase cardio stress and may require more recovery.
Wrist devices can be inaccurate during intervals. Use a chest strap for better precision.
At age 30, estimated max HR is 190 bpm. An average workout HR of 145 bpm is about 76% of max, which is a cardio-focused zone.
It depends on goal. Many aerobic workouts sit around 60% to 80% of estimated max heart rate.
Lower to moderate zones use a higher proportion of fat, but total calorie balance still matters for fat loss.
A very high percentage of max heart rate, especially with symptoms, should be treated cautiously.
Estimate max heart rate, then multiply by zone percentages or use the Karvonen heart-rate-reserve method.
It estimates target heart rate as resting HR plus a percentage of the difference between max HR and resting HR.
| Metric | Meaning |
|---|---|
| Max HR | Estimated upper heart-rate limit |
| Intensity | Average HR as percent of max |
| Zone | Training classification |
| Risk | Potential overtraining stress |