Your training zones, beat by beat.
Enter your age and resting heart rate and get all five heart rate training zones instantly, personalized with the Karvonen formula, along with your estimated maximum heart rate and heart rate reserve.
Your details
Your current age in years.
Your heart rate at rest, measured in the morning before getting up.
Max HR is estimated as 220 - age. Zones use the Karvonen formula: Target HR = (Max HR - Resting HR) x Intensity% + Resting HR. Results update as you type.
What your zones mean
Your five heart rate zones
Key numbers for your training
Zone table at your age
Karvonen targets use your resting heart rate, classic targets use max HR percentage alone. The highlighted row is the aerobic zone most plans build around.
| Zone | Intensity | Karvonen (bpm) | Classic (bpm) |
|---|
Target heart rate, explained
Understanding Heart Rate Zones
Heart rate zones divide your exercise intensity into five ranges based on percentage of maximum heart rate. Zone 1 (50-60%) is recovery, Zone 2 (60-70%) is fat burning, Zone 3 (70-80%) is aerobic endurance, Zone 4 (80-90%) is anaerobic threshold, and Zone 5 (90-100%) is maximum effort. Each zone produces different training adaptations.
The Karvonen Formula
This calculator uses the Karvonen formula, which accounts for your resting heart rate: Target HR = ((Max HR - Resting HR) × Intensity%) + Resting HR. This is more accurate than simply multiplying max heart rate by a percentage because it personalizes the zones based on your current fitness level.
Benefits of Zone Training
Training in specific heart rate zones allows you to target specific fitness adaptations. Zone 2 training builds aerobic base and burns fat efficiently. Zone 3 improves cardiovascular fitness. Zone 4 increases lactate threshold and speed. Most training plans recommend spending 80% of training time in Zones 1-2 and 20% in Zones 3-5.
Measuring Your Heart Rate
Measure resting heart rate first thing in the morning before getting out of bed. Count your pulse for 60 seconds or use a fitness tracker. During exercise, chest strap monitors are most accurate, followed by optical wrist sensors. Average resting heart rate for adults is 60-100 bpm, with fitter individuals typically having lower rates.
Common questions
What is maximum heart rate?
Maximum heart rate is estimated as 220 minus your age. This is a population average, individual maximum heart rate can vary by 10-15 beats per minute. The only way to determine your true max heart rate is through a supervised maximal exercise test.
Which heart rate zone is best for fat loss?
Zone 2 (60-70% max HR) burns the highest percentage of calories from fat. However, higher-intensity zones burn more total calories per minute. For overall fat loss, total calorie burn matters most. A mix of Zone 2 and higher-intensity intervals is most effective.
Is a lower resting heart rate better?
Generally, yes. A lower resting heart rate indicates a more efficient heart. Well-trained athletes may have resting heart rates of 40-60 bpm. An average adult resting heart rate is 60-100 bpm. A resting heart rate consistently above 100 bpm should be discussed with a doctor.
How accurate is the 220-minus-age formula?
The 220-minus-age formula has a standard deviation of about 10-12 bpm, meaning your actual max heart rate could be significantly higher or lower than predicted. It is a useful starting point but should not be treated as exact. Adjust zones based on your perceived exertion during workouts.
This calculator provides estimates for healthy adults, not medical advice. The 220 minus age formula is a population average and your true maximum heart rate may differ by 10-15 bpm. Do not use these numbers to make medical decisions on your own: talk to a doctor before starting a new exercise program, especially if you have a heart condition, take medication that affects heart rate (such as beta blockers), are pregnant, or experience chest pain, dizziness or shortness of breath during exercise.