Heart Rate Zone Calculator
Leave blank to calculate using the standard formula (220 – Age).
Understanding Heart Rate Zones
Your heart rate is a vital indicator of your cardiovascular health and exercise intensity. Training within specific heart rate zones allows you to optimize your workouts for different goals, whether it's improving endurance, building strength, or enhancing recovery. This calculator helps you determine your personal heart rate zones based on your age or a manually entered maximum heart rate.
How Heart Rate Zones Are Calculated
The most common method for determining heart rate zones involves first estimating your Maximum Heart Rate (MHR) and then calculating percentage-based zones around it.
-
Maximum Heart Rate (MHR): The highest number of times your heart can beat in one minute during maximal physical exertion. The most widely used formula to estimate MHR is:
MHR = 220 – Age
For example, a 40-year-old individual would have an estimated MHR of 220 – 40 = 180 bpm.
Alternatively, you can enter a manually determined MHR if you know it from a stress test or other reliable measurement.
-
Heart Rate Zones: Once MHR is established, zones are typically calculated as a percentage of MHR. A common 5-zone model is used by many fitness organizations and is what this calculator employs:
- Zone 1: Very Light (50-60% of MHR) – Recovery, cool-down.
- Zone 2: Light (60-70% of MHR) – Aerobic base, endurance building, fat burning.
- Zone 3: Moderate (70-80% of MHR) – Aerobic fitness, improved endurance.
- Zone 4: Hard (80-90% of MHR) – Anaerobic threshold, improved speed and power.
- Zone 5: Maximum (90-100% of MHR) – High-intensity interval training (HIIT), peak performance.
Example Calculation
Let's consider a 35-year-old individual:
- Estimated MHR: 220 – 35 = 185 bpm
- Zone 1 (50-60%): 185 * 0.50 = 92.5 bpm to 185 * 0.60 = 111 bpm
- Zone 2 (60-70%): 185 * 0.60 = 111 bpm to 185 * 0.70 = 129.5 bpm
- Zone 3 (70-80%): 185 * 0.70 = 129.5 bpm to 185 * 0.80 = 148 bpm
- Zone 4 (80-90%): 185 * 0.80 = 148 bpm to 185 * 0.90 = 166.5 bpm
- Zone 5 (90-100%): 185 * 0.90 = 166.5 bpm to 185 * 1.00 = 185 bpm
Why Use Heart Rate Zones?
Training within specific heart rate zones allows for a more scientific and targeted approach to exercise:
- Goal Specificity: Different zones target different physiological systems. For example, Zone 2 is excellent for building an aerobic base and improving fat metabolism, while Zone 4 is crucial for increasing your lactate threshold and improving race pace.
- Preventing Overtraining: By monitoring your heart rate, you can ensure you're not consistently pushing too hard, which can lead to burnout, injury, and diminished performance.
- Tracking Progress: As your fitness improves, your resting heart rate may decrease, and you may be able to sustain higher intensities for longer. Monitoring your heart rate response to exercise can help you see these improvements over time.
- Personalized Workouts: This calculator provides a personalized framework for designing your training sessions based on your current fitness level.
Remember to consult with a healthcare professional before starting any new exercise program.
Your Calculated Heart Rate Zones:
';
resultHTML += 'Maximum Heart Rate (MHR): ' + finalMHR + ' bpm
';
resultHTML += 'Zone 1 (Very Light): ' + zone1_low + ' – ' + zone1_high + ' bpm (50-60% of MHR)
';
resultHTML += 'Zone 2 (Light): ' + zone2_low + ' – ' + zone2_high + ' bpm (60-70% of MHR)
';
resultHTML += 'Zone 3 (Moderate): ' + zone3_low + ' – ' + zone3_high + ' bpm (70-80% of MHR)
';
resultHTML += 'Zone 4 (Hard): ' + zone4_low + ' – ' + zone4_high + ' bpm (80-90% of MHR)
';
resultHTML += 'Zone 5 (Maximum): ' + zone5_low + ' – ' + zone5_high + ' bpm (90-100% of MHR)
';
resultDiv.innerHTML = resultHTML;
}