Heart Rate Zone Calculator
Free Heart Rate Zone Calculator using the Karvonen formula. Calculate your 5 heart rate training zones based on age and resting heart rate.
About This Calculator
Training in the right heart rate zones maximizes your workout efficiency. The Karvonen formula uses your heart rate reserve (max HR minus resting HR) to calculate personalized training zones.
Frequently Asked Questions
What are heart rate zones?
Heart rate zones are intensity ranges for cardiovascular exercise. Zone 1 (50-60%): Very light, recovery. Zone 2 (60-70%): Light, endurance. Zone 3 (70-80%): Moderate, aerobic. Zone 4 (80-90%): Hard, threshold. Zone 5 (90-100%): Maximum effort.
What is the Karvonen formula?
The Karvonen formula calculates target heart rate using heart rate reserve (HRR): Target HR = ((Max HR - Resting HR) x %Intensity) + Resting HR. This is more accurate than percentage of max HR alone because it accounts for your resting heart rate.
What zone should I train in?
Zone 2 (endurance) for 80% of training - builds aerobic base. Zone 4 (threshold) for 10-15% - improves lactate tolerance. Zone 5 (max) for 5% - develops top-end speed. Beginners should focus on Zone 2 for the first 3-6 months.
How do I measure my resting heart rate?
Measure your resting HR first thing in the morning before getting out of bed. Take your pulse for 60 seconds (or 30 seconds x 2). The average adult resting HR is 60-100 bpm, while athletes often have 40-60 bpm.