About Heart Rate Zone Calculator
Find your target heart rate zones for fat burn, cardio, and peak training. Enter your age and resting heart rate to get your max HR and personalized training ranges. Free.
How to use
- Enter your age. The calculator estimates your maximum heart rate using the standard formula (220 minus age). A 35-year-old has an estimated max HR of 185 beats per minute. More precise formulas like Gulati (for women) and Tanaka are also available for comparison.
- Optionally enter your resting heart rate for more personalized training zones using the Karvonen method. Measure your resting HR by sitting quietly for 5 minutes and counting your pulse for 60 seconds, ideally first thing in the morning before getting out of bed. Average resting HR for adults is 60-100 bpm; fit individuals may be 40-60 bpm.
- View your five heart rate training zones, each targeting a different physiological adaptation. Zone 1 (50-60% max) is warm-up and recovery. Zone 2 (60-70%) is fat burning and base endurance. Zone 3 (70-80%) is aerobic conditioning. Zone 4 (80-90%) is lactate threshold and race pace. Zone 5 (90-100%) is maximum effort and speed.
- Select zones based on your training goal. For fat loss and general health, spend most training time in Zones 2-3. For race performance, include Zone 4 intervals. For maximum cardiovascular improvement, incorporate short Zone 5 efforts with adequate recovery between intervals.
- Track your heart rate during workouts using a chest strap monitor (most accurate) or wrist-based optical sensor (convenient but less precise during high-intensity movement). Compare your actual training zones against the calculated targets to ensure you are training at the right intensity.
- Monitor your resting heart rate over time. A declining resting HR indicates improving cardiovascular fitness — a drop from 72 bpm to 62 bpm over 3 months reflects meaningful aerobic adaptation. An unusually elevated resting HR (10+ bpm above normal) can indicate overtraining, illness, or insufficient recovery.
Frequently asked questions
How do I calculate my maximum heart rate?
The simplest formula is 220 minus your age: a 40-year-old has an estimated max HR of 180 bpm. More accurate formulas include Tanaka (208 - 0.7 x age), which gives 180 for a 40-year-old, and Gulati (206 - 0.88 x age), developed specifically for women, giving 171 for a 40-year-old woman. All formulas are estimates with a standard deviation of 10-12 bpm, meaning your actual max HR could be 10-12 beats higher or lower. The only way to determine your true max HR is a supervised maximal exercise test, but the calculated estimate is sufficient for training zone planning.
What heart rate zone burns the most fat?
Zone 2 (60-70% of max HR) burns the highest percentage of calories from fat. However, higher-intensity zones burn more total calories per minute, including more total fat calories despite a lower fat percentage. A 30-minute Zone 2 jog at 130 bpm might burn 250 calories (60% fat = 150 fat calories). A 30-minute Zone 4 run at 165 bpm might burn 400 calories (40% fat = 160 fat calories). For weight loss, total calories burned matters more than the fat percentage. Zone 2 training remains valuable for building aerobic base, recovery, and enabling longer workout durations. Use the
Calorie Calculator to see your full daily energy expenditure including exercise calories.
What is the Karvonen formula?
The Karvonen formula personalizes training zones using your heart rate reserve (HRR), which accounts for your resting heart rate. HRR = Max HR - Resting HR. Target HR = (HRR x desired intensity%) + Resting HR. For a 40-year-old with max HR 180 and resting HR 65: HRR = 115. Zone 2 (60-70%): (115 x 0.60) + 65 = 134 to (115 x 0.70) + 65 = 146 bpm. Without the Karvonen adjustment, Zone 2 would be 108-126 bpm, which feels too easy for a fit person. The Karvonen method produces more accurate and individually appropriate training zones than percentage-of-max alone.
How do I measure my resting heart rate?
The most accurate method: immediately upon waking (before getting out of bed), lie still for 2 minutes, then count your pulse at the wrist (radial artery) or neck (carotid artery) for a full 60 seconds. Take the measurement on 3-5 consecutive mornings and average the results. Avoid measuring after caffeine, alcohol, a poor night's sleep, or when stressed, as these elevate resting HR. Normal resting HR for adults is 60-100 bpm. Well-trained endurance athletes often have resting HRs of 40-55 bpm. A resting HR above 100 bpm (tachycardia) should be discussed with a physician.
Is it dangerous to exercise at my max heart rate?
Brief efforts at or near maximum heart rate are safe for healthy adults and are a normal part of high-intensity interval training (HIIT), sprinting, and competitive sports. However, sustained exercise at max HR is unsustainable (you can only maintain it for 30-60 seconds) and unnecessary for most fitness goals. The risk is not the high heart rate itself but rather underlying cardiac conditions that may not be apparent. Adults over 40 beginning an intense exercise program, people with family history of heart disease, and anyone experiencing chest pain, dizziness, or shortness of breath during exercise should consult a physician before high-intensity training.
Why is my heart rate different from the chart?
The 220-minus-age formula estimates population averages, not individual values. Your actual max HR can be 10-15 bpm higher or lower than the estimate due to genetics, fitness level, and cardiovascular health. If you consistently hit 190 bpm during hard efforts despite a calculated max of 180, your true max is likely near 190 — recalculate your zones using that number. Medications (particularly beta-blockers) significantly reduce achievable heart rate and require adjusted training zones. Environmental factors like heat, humidity, altitude, dehydration, and caffeine also shift heart rate response during exercise.
What is a good resting heart rate?
For adults, the American Heart Association classifies resting HR of 60-100 bpm as normal, with lower generally indicating better cardiovascular fitness. Athletes often have resting HRs of 40-60 bpm because their hearts pump more blood per beat (higher stroke volume), requiring fewer beats per minute. Average values by fitness level: sedentary 70-80 bpm, moderately fit 60-70 bpm, highly fit 50-60 bpm, elite athlete 40-50 bpm. Resting HR below 60 bpm (bradycardia) is normal for fit individuals but should be evaluated by a doctor if accompanied by dizziness, fatigue, or fainting.
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