⚡ Quick Answer
Your maximum heart rate = 220 minus your age. Heart rate zones: Zone 1 (50-60% max) = warm-up. Zone 2 (60-70%) = fat burning. Zone 3 (70-80%) = aerobic fitness. Zone 4 (80-90%) = anaerobic/high intensity. Zone 5 (90-100%) = maximum effort. A 30-year-old has max HR of 190 bpm, so Zone 2 = 114-133 bpm.
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❤️ Heart Rate Zone Calculator

Calculate your heart rate zones for optimal training. Find your fat-burning zone, aerobic zone, and maximum heart rate. Essential for running, cycling, swimming, and any cardio training.

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💡 Measure resting heart rate first thing in the morning before getting out of bed. Count beats for 60 seconds.
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🦉Owl's Explanation
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✅ Trusted Tool
The 365tool.net Heart Rate Zone Calculator uses the standard 220-age formula and Karvonen Heart Rate Reserve method used by sports scientists and fitness professionals. Free for all athletes and fitness enthusiasts.

🤔 How Does This Work?

Our Heart Rate Zone Calculator uses two formulas:

  • Basic: Max HR = 220 - Age. Each zone = % of Max HR
  • Karvonen: Heart Rate Reserve (HRR) = Max HR - Resting HR. Target = (HRR x Intensity%) + Resting HR

Five zones: Zone 1 (50-60%), Zone 2 (60-70%), Zone 3 (70-80%), Zone 4 (80-90%), Zone 5 (90-100%). Karvonen zones feel more accurate because they account for individual cardiovascular fitness.

❓ Frequently Asked Questions

What are heart rate zones?
Heart rate zones are ranges of heart rate that correspond to different exercise intensities. Training in different zones has different effects: Zone 2 builds aerobic base and burns fat, Zone 4 builds speed and power, Zone 5 builds peak performance. Most training should be in Zone 2.
What is the Karvonen formula?
The Karvonen (Heart Rate Reserve) formula gives more personalized zones by accounting for your resting heart rate: Target HR = ((Max HR - Resting HR) x Intensity%) + Resting HR. This is more accurate because two people with the same age but different resting HRs have different cardiovascular fitness levels.
What is the fat-burning zone?
Zone 2 (60-70% max HR) is often called the fat-burning zone because fat provides a higher percentage of energy at this intensity. However, higher intensities burn MORE total calories — just a lower percentage from fat. For weight loss, total calorie burn matters more than fat percentage.
What is a good resting heart rate?
Normal resting HR: 60-100 bpm. Athletes: 40-60 bpm. Excellent cardiovascular fitness: below 60. The lower your resting HR (while healthy), the more efficient your heart is. Regular aerobic exercise lowers resting HR over months and years.
How do I train in my zones?
Wear a heart rate monitor or use a smartwatch. For Zone 2: you should be able to hold a conversation. Zone 3-4: breathing is heavy, speaking is difficult. Zone 5: maximum effort, only sustainable for short intervals. Most training should be 80% Zone 1-2, 20% Zone 3-5 (the 80/20 rule).
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❓ FAQ
What are heart rate zones?
Heart rate zones are ranges of heart rate that correspond to different exercise intensities. Training in different zones has different effects: Zone 2 builds aerobic base and burns fat, Zone 4 builds speed and power, Zone 5 builds peak performance. Most training should be in Zone 2.
What is the Karvonen formula?
The Karvonen (Heart Rate Reserve) formula gives more personalized zones by accounting for your resting heart rate: Target HR = ((Max HR - Resting HR) x Intensity%) + Resting HR. This is more accurate because two people with the same age but different resting HRs have different cardiovascular fitness levels.
What is the fat-burning zone?
Zone 2 (60-70% max HR) is often called the fat-burning zone because fat provides a higher percentage of energy at this intensity. However, higher intensities burn MORE total calories — just a lower percentage from fat. For weight loss, total calorie burn matters more than fat percentage.
What is a good resting heart rate?
Normal resting HR: 60-100 bpm. Athletes: 40-60 bpm. Excellent cardiovascular fitness: below 60. The lower your resting HR (while healthy), the more efficient your heart is. Regular aerobic exercise lowers resting HR over months and years.
How do I train in my zones?
Wear a heart rate monitor or use a smartwatch. For Zone 2: you should be able to hold a conversation. Zone 3-4: breathing is heavy, speaking is difficult. Zone 5: maximum effort, only sustainable for short intervals. Most training should be 80% Zone 1-2, 20% Zone 3-5 (the 80/20 rule).