Heart Rate Zone Calculator
Calculate your 5 heart rate training zones based on age and resting heart rate to optimize every workout.
Quick Answer
Max heart rate is estimated as 220 minus your age. Zone 2 (60-70% of max) is ideal for fat burning and endurance. Zone 4 (80-90%) builds speed and lactate threshold. For more accuracy, enter your resting heart rate to use the Karvonen method, which accounts for your fitness level.
Measure resting HR first thing in the morning before getting out of bed.
Your Heart Rate Zones
Recovery, warm-up, active rest
Fat burning, endurance base building
Aerobic fitness, tempo running
Lactate threshold, speed endurance
VO2 max, maximum performance
Training Recommendations
| Zone | Effort Feel | Duration |
|---|---|---|
| Zone 1 | Very easy, can hold full conversation | 20-60 min |
| Zone 2 | Comfortable, can speak in sentences | 30-120 min |
| Zone 3 | Moderate, can speak short phrases | 20-60 min |
| Zone 4 | Hard, can only say a few words | 10-30 min intervals |
| Zone 5 | All-out, cannot speak | 30 sec - 3 min intervals |
About This Tool
Heart rate zone training is one of the most effective ways to ensure your workouts match your fitness goals. By training in specific heart rate zones, you can target fat burning, build aerobic endurance, improve speed, or push your maximum capacity. This calculator provides your personalized zones using either the standard age-based formula or the more precise Karvonen method.
Standard vs. Karvonen Method
The standard method simply multiplies your maximum heart rate (220 minus age) by the zone percentages. It is simple and works for most people. The Karvonen method uses your heart rate reserve (max HR minus resting HR) and adds your resting HR back, which accounts for your current fitness level. A well-trained athlete with a resting heart rate of 50 will get different zones than a beginner at 80 BPM, even at the same age.
Why Zone 2 Training Matters
Zone 2 has gained significant attention in recent years, championed by endurance coaches and longevity researchers. Training in Zone 2 (60-70% of max HR) builds mitochondrial density, improves fat oxidation, and strengthens your aerobic base. Many elite athletes spend 80% of their training time in Zone 2, a principle known as polarized training. For recreational exercisers, Zone 2 work means you can exercise longer, recover faster, and build a foundation for higher-intensity work.
Limitations of the 220 - Age Formula
The 220-minus-age formula has a standard deviation of about 10-12 BPM. This means your actual max heart rate could be up to 12 BPM higher or lower than predicted. For precise max HR, a graded exercise test with a sports medicine doctor is the gold standard. Alternatively, a field test such as a 3-minute all-out run on a track can provide a reasonable estimate. Never attempt a max HR test without proper warm-up and medical clearance.
How to Measure Resting Heart Rate
For the most accurate resting heart rate measurement, check your pulse first thing in the morning before getting out of bed. Count beats for 60 seconds using your index and middle fingers on the inside of your wrist (radial pulse) or the side of your neck (carotid pulse). Repeat for 3 consecutive mornings and average the results. A lower resting heart rate generally indicates better cardiovascular fitness.
Frequently Asked Questions
What heart rate zone is best for fat burning?
How accurate is the 220-minus-age formula?
How do I know which zone I'm in during exercise?
How much time should I spend in each zone?
Does medication affect heart rate zones?
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