Health & Fitness
Target Heart Rate Calculator
Calculate your optimal heart rate training zones based on your age and resting heart rate.
Reviewed by the calculator.uk.com Team · Last reviewed 12 August 2026 · Our methodology
Enter your age and resting heart rate to calculate your target heart rate zones
Related to Target Heart Rate Calculator
The Target Heart Rate Calculator uses two scientifically validated formulas to determine your optimal heart rate training zones: the Tanaka formula for maximum heart rate and the Karvonen formula for heart rate reserve. This combination provides more accurate and personalized training zones compared to older methods.
Maximum Heart Rate Calculation
We use the Tanaka formula (2001): HRmax = 208 - (0.7 × age). This formula is more accurate than the traditional 220-age formula, especially for older adults and has been validated across diverse populations.
Heart Rate Reserve (HRR)
The Karvonen formula uses your Heart Rate Reserve (HRR = Maximum Heart Rate - Resting Heart Rate) to calculate personalized training zones. This method accounts for individual fitness levels by incorporating your resting heart rate.
Your target heart rate zones are calculated as percentages of your heart rate reserve, added to your resting heart rate. Each zone serves a specific training purpose:
Zone 1: Recovery (50-60% HRR)
Ideal for warm-up, cool-down, and recovery training. This zone improves basic endurance and fat burning.
Zone 2: Aerobic (60-70% HRR)
The "conversational pace" zone. Builds aerobic fitness and improves fat metabolism.
Zone 3: Endurance (70-80% HRR)
Improves cardiovascular fitness and endurance. Training becomes more challenging but sustainable.
Zone 4: Threshold (80-90% HRR)
High-intensity training that improves lactate threshold and maximum performance.
Zone 5: Anaerobic (90-100% HRR)
Maximum effort zone for short intervals. Improves maximum performance and speed.
1. How do I measure my resting heart rate?
Measure your resting heart rate first thing in the morning before getting out of bed. Count your pulse for 60 seconds, or count for 30 seconds and multiply by 2. For best accuracy, take measurements over several days and use the average.
2. Why are target heart rate zones important?
Training zones help you optimize your workouts by ensuring you're exercising at the right intensity for your specific goals, whether that's fat burning, endurance building, or performance improvement. They also help prevent overtraining and undertraining.
3. How often should I train in each zone?
A balanced training program typically includes: 50-60% in Zones 1-2 for base fitness, 30-40% in Zone 3 for endurance, and 10-20% in Zones 4-5 for high-intensity work. The exact distribution depends on your fitness goals and current condition.
4. Do these zones work for everyone?
While these zones are based on scientific formulas, individual factors like fitness level, medications, and health conditions can affect your heart rate response. Always consult with a healthcare provider before starting a new exercise program.
5. What is the scientific source for this calculator?
Maximum heart rate here is estimated with the Tanaka formula, HRmax = 208 - (0.7 x age), published by Tanaka, Monahan and Seals in the Journal of the American College of Cardiology (2001) as a more accurate alternative to the older 220-minus-age rule of thumb. The training zones themselves come from the Karvonen method (Karvonen MJ, Kentala E, Mustala O., Annales Medicinae Experimentalis et Biologiae Fenniae, 1957), which factors in resting heart rate via the heart rate reserve calculation rather than using percentages of maximum heart rate alone. Both formulas remain standard reference points in exercise physiology, though actual heart rate response still varies with fitness level, medication, and individual physiology.