❤️ Heart Rate Zone Calculator
Calculate your 5 training heart rate zones to optimize fat burning, cardio endurance, and peak performance. Uses both the standard and Karvonen methods.
Understanding Heart Rate Zones
Heart rate zones are ranges of beats per minute that correspond to different exercise intensities. Training in the right zone helps you achieve specific fitness goals efficiently.
The 5 Training Zones
| Zone | % Max HR | Intensity | Benefits |
|---|---|---|---|
| Zone 1 | 50-60% | Very Light | Recovery, warm-up, basic fitness |
| Zone 2 | 60-70% | Light | Fat burning, endurance base building |
| Zone 3 | 70-80% | Moderate | Aerobic capacity, cardio fitness |
| Zone 4 | 80-90% | Hard | Anaerobic threshold, speed endurance |
| Zone 5 | 90-100% | Maximum | Max performance, VO2max, sprints |
Max Heart Rate Formulas
- Standard: Max HR = 220 − age (simple, widely used)
- Tanaka: Max HR = 208 − (0.7 × age) (more accurate for older adults)
- Karvonen: Uses heart rate reserve (Max HR − Resting HR) for personalized zones
The 80/20 Rule
Elite endurance athletes typically follow the 80/20 rule: 80% of training time in Zone 1-2 (easy, conversational pace) and 20% in Zone 3-5 (moderate to hard). This approach builds a strong aerobic base while avoiding overtraining.
Training Tips
- Weight loss? Zone 2 burns a higher percentage of fat calories, but Zone 3-4 burns more total calories
- Building endurance? Spend most time in Zone 2 — it builds mitochondria and capillary density
- Getting faster? Add Zone 4 intervals (tempo runs, threshold work)
- Max performance? Zone 5 for short intervals (30s-2min) with full recovery between sets
Frequently Asked Questions
The standard formula is 220 minus your age. For a more accurate estimate, the Tanaka formula uses 208 - (0.7 × age). The most accurate method is a supervised maximal exercise test with a healthcare provider.
Zone 2 (60-70% max HR) is the traditional "fat burning zone" where a higher percentage of calories come from fat. However, higher intensity zones burn more total calories per minute, which can be more effective for overall fat loss.
The Karvonen formula uses heart rate reserve (HRR = max HR - resting HR) for more personalized zones: Target HR = ((max HR - resting HR) × intensity%) + resting HR. It accounts for your fitness level through the resting heart rate.
For general fitness, follow the 80/20 rule: 80% of training in Zone 1-2 (easy), 20% in Zone 3-5. For beginners, start with Zone 1-2 exclusively for 4-6 weeks before adding intensity.
Zone 5 is very intense and should only be done by healthy, trained individuals for short durations (30s-2min). Consult a doctor before high-intensity training, especially if you have heart conditions, are over 45, or are new to exercise.
Normal resting heart rate is 60-100 bpm. Well-trained endurance athletes often have 40-60 bpm. Measure yours first thing in the morning, before getting out of bed, for the most accurate reading.