Heart Rate Zones Calculator
Find your maximum heart rate and personalized training zones.
Medical Disclaimer: This tool is for educational purposes only. It does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting a new exercise program.
Understanding Heart Rate Training Zones
Heart rate zones are ranges of heartbeats per minute that correspond to different exercise intensities. Training within specific zones helps you optimize workouts for endurance, fat burning, or peak performance. Zones are typically calculated as a percentage of your maximum heart rate (HRmax).
Maximum Heart Rate
The most common formula is HRmax = 220 − age. While simple and widely used, individual variation can be significant. More refined formulas (Tanaka, Gulati for women) exist, but the "220 minus age" method remains the standard starting point.
The Karvonen Method
When a resting heart rate is provided, this calculator uses the Karvonen formula, which accounts for your fitness level by using heart rate reserve (HRR = HRmax − resting HR). Target HR = resting HR + (HRR × intensity%). This method provides more personalized zones compared to simple percentage-of-max calculations.
The Five Training Zones
- Zone 1 — Recovery (50–60%): Very light activity. Ideal for warm-ups, cool-downs, and active recovery days.
- Zone 2 — Fat Burn (60–70%): Light aerobic activity. Builds aerobic base and improves fat metabolism. Sustainable for long durations.
- Zone 3 — Aerobic (70–80%): Moderate intensity. Improves cardiovascular fitness and aerobic capacity.
- Zone 4 — Threshold (80–90%): Hard effort near the anaerobic threshold. Improves speed endurance and lactate tolerance.
- Zone 5 — Maximum (90–100%): All-out effort. Develops maximum performance and speed. Only sustainable for very short periods.
Frequently Asked Questions
What are the five heart rate zones?
Zone 1 (50–60% max HR): Recovery/warm-up. Zone 2 (60–70%): Fat burning and endurance base. Zone 3 (70–80%): Aerobic fitness and stamina. Zone 4 (80–90%): Anaerobic threshold and speed. Zone 5 (90–100%): Maximum effort and VO2max training. Each zone targets different energy systems.
How do I calculate my maximum heart rate?
The simplest formula is 220 minus your age. However, this calculator also uses the Tanaka formula (208 − 0.7 × age) which is considered more accurate for older adults, and the Gulati formula (206 − 0.88 × age) specifically validated for women.
What heart rate zone burns the most fat?
Zone 2 (60–70% of max HR) is traditionally called the 'fat-burning zone' because a higher percentage of calories come from fat at this intensity. However, higher-intensity zones burn more total calories per minute. For weight loss, total calorie expenditure matters more than the percentage from fat.
Is resting heart rate a sign of fitness?
Generally, yes. A lower resting heart rate usually indicates better cardiovascular fitness because the heart pumps more blood per beat. Athletes often have resting heart rates between 40–60 bpm. A resting heart rate consistently above 100 bpm (tachycardia) should be discussed with a doctor.
Can Apple Watch track heart rate zones?
Apple Watch tracks heart rate continuously but shows limited zone information. HeartLab provides detailed heart rate analysis from ECG recordings, including precise beat-to-beat intervals that reveal heart rate variability patterns invisible in standard heart rate monitoring.
Track Your Heart Rate in Real Time
HeartLab monitors your heart rate directly from Apple Watch with clinical-grade precision — giving you insights your doctor would appreciate.
