- Enter your age. Maximum heart rate (MHR) is estimated as 220 minus your age. A 35-year-old has an estimated MHR of 185 bpm. This is the upper ceiling used to define all training zones.
- Enter your resting heart rate. Measure first thing in the morning before getting out of bed. Average readings from 3 consecutive mornings for accuracy. A normal resting HR is 60-100 bpm; athletes often see 40-60 bpm.
- Choose a calculation method. Karvonen (Heart Rate Reserve) accounts for your resting HR and gives more personalized zones, especially useful for athletes. Simple % of Max HR works for general fitness without a resting HR measurement.
Target Heart Rate Calculator
Calculate your maximum and target heart rate zones for fat burn, cardio, and peak training.
Karvonen uses resting HR for more personalized zones (recommended).
Maximum Heart Rate
190 bpm
Based on 220 - age formula
Heart Rate Training Zones
Zone 1 - Recovery
Light activity, active recovery
Zone 2 - Fat Burn
Aerobic base, fat oxidation
Zone 3 - Cardio
Aerobic endurance, moderate effort
Zone 4 - Hard
Lactate threshold, hard effort
Zone 5 - Max
Maximum effort, VO2 max
How to Find Your Heart Rate Zones
Heart Rate Zone Formulas
Max HR (estimated): 220 - age Karvonen (HRR method): Heart Rate Reserve (HRR) = Max HR - Resting HR Target HR = (HRR × Zone%) + Resting HR Example: age 35, resting HR 65 Max HR = 220 - 35 = 185 bpm HRR = 185 - 65 = 120 Zone 3 (70%): (120 × 0.70) + 65 = 149 bpm
Training zones and their purposes:
| Zone | % Max HR | Effort | Purpose |
|---|---|---|---|
| Zone 1 | 50-60% | Very light | Recovery, warm-up |
| Zone 2 | 60-70% | Light | Fat burning, aerobic base |
| Zone 3 | 70-80% | Moderate | Aerobic capacity, tempo |
| Zone 4 | 80-90% | Hard | Lactate threshold, race pace |
| Zone 5 | 90-100% | Max | Speed, VO2 max intervals |
Frequently Asked Questions
Heart rate training zones are percentage ranges of your maximum heart rate, each targeting different physiological adaptations. Zone 2 (60-70%) builds aerobic base and burns fat. Zone 3-4 (70-90%) improves cardiovascular capacity and lactate threshold. Zone 5 (90-100%) develops maximum speed and VO2 max. Monitoring zones during exercise ensures you are training at the right intensity for your specific goals, rather than always running at moderate effort.
The Karvonen method uses Heart Rate Reserve (HRR = max HR minus resting HR) to calculate training zones. This personalizes zones based on your cardiovascular fitness level. A sedentary person and a trained athlete may have the same max HR but very different resting HRs, meaning the same absolute heart rate represents different relative efforts. Adding resting HR back into the calculation produces more accurate training prescriptions, especially for athletes with low resting heart rates.
Zone 2 (60-70% max HR) burns the highest proportion of calories from fat (50-70% of fuel from fat vs. carbohydrates). However, higher intensity zones burn more total calories per hour, which matters more for overall fat loss. Zone 2 is excellent for building aerobic base, improving fat oxidation efficiency, and supporting heart health without excessive fatigue. Most endurance coaches recommend spending 80% of training time in Zone 2 with 20% in Zones 4-5.
The 220-age formula is a statistical average with a standard deviation of about 10-12 bpm. Your actual max HR may differ by 10-20 bpm from the estimate. The Tanaka formula (208 - 0.7 × age) tends to be more accurate for older adults. The most accurate way to find your max HR is a maximal exercise test on a treadmill or bike, though this should be done under medical supervision if you have any cardiovascular risk factors.
A normal resting HR for adults is 60-100 bpm. Well-trained endurance athletes often have resting HRs of 40-60 bpm because their hearts pump more blood per beat. A consistently elevated resting HR above 100 bpm (tachycardia) can indicate stress, dehydration, illness, thyroid issues, or cardiovascular problems. A sudden increase of 5-10 bpm above your usual resting HR often signals the onset of overtraining, illness, or inadequate recovery.