Calculate target heart rate zones for training
The Karvonen method uses your heart rate reserve (max HR - resting HR) for more personalized zones. Formula: Target HR = ((Max HR - Resting HR) × %Intensity) + Resting HR. It's more accurate than simple percentage of max HR.
Measure your pulse first thing in the morning before getting out of bed, for several days. Count beats for 60 seconds or for 15 seconds and multiply by 4. Average the readings for your true resting heart rate.
Zone 2 (60-70% max HR) burns the highest percentage of calories from fat. However, higher intensity zones burn more total calories and fat overall. A mix of zones in your training is most effective for fat loss.
The formula 220 - age estimates maximum heart rate. While simple, it's an approximation with ±10-12 bpm variability. More accurate formulas exist (Tanaka: 208 - 0.7×age), or test your actual max HR under supervision.
Most training (80%) should be in zones 1-2 for aerobic base. Reserve 20% for zones 4-5 intensity work. This polarized approach builds endurance while developing speed. Avoid spending too much time in zone 3.
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