Target Heart Rate & Zone Calculator
Your Calculated Results
Maximum Heart Rate (MHR): BPM
Heart Rate Reserve (HRR): BPM
| Training Zone | Intensity | Heart Rate Range |
|---|---|---|
| Zone 1: Very Light | 50% – 60% | |
| Zone 2: Light (Fat Burn) | 60% – 70% | |
| Zone 3: Moderate (Aerobic) | 70% – 80% | |
| Zone 4: Hard (Anaerobic) | 80% – 90% | |
| Zone 5: Maximum (V02 Max) | 90% – 100% |
Understanding Your Heart Rate Training Zones
Training with a heart rate calculator is one of the most effective ways to ensure your workouts align with your fitness goals. Whether you are trying to lose weight, improve cardiovascular endurance, or increase your speed, knowing your heart rate zones allows you to train "smarter, not harder."
The Karvonen Formula: Why It Matters
This calculator uses the Karvonen Formula, which is widely considered more accurate than simple percentage-of-max-heart-rate calculations. While the standard formula (220 – age) gives a generic maximum, the Karvonen method incorporates your Resting Heart Rate (RHR) to calculate your Heart Rate Reserve (HRR). This accounts for your current fitness level, as a lower resting heart rate usually indicates a more efficient cardiovascular system.
Breaking Down the Five Intensity Zones
- Zone 1 (50-60%): Very Light. Ideal for warm-ups, cool-downs, and active recovery. It improves overall health but doesn't build significant endurance.
- Zone 2 (60-70%): Light / Fat Burn. This is the "sweet spot" for long-duration exercise. At this intensity, the body primarily uses stored fat for fuel and builds basic aerobic endurance.
- Zone 3 (70-80%): Moderate / Aerobic. This zone improves your cardiovascular capacity. You'll breathe harder but should still be able to speak in short sentences.
- Zone 4 (80-90%): Hard / Anaerobic. Training here improves your lactate threshold. You will feel a "burn" in your muscles as your body begins to produce energy without sufficient oxygen.
- Zone 5 (90-100%): Maximum. This is peak effort, usually reserved for interval training (HIIT). It develops maximum performance and speed but can only be sustained for very short periods.
Example Calculation
If a 40-year-old individual has a resting heart rate of 60 BPM:
- Max Heart Rate (MHR): 220 – 40 = 180 BPM.
- Heart Rate Reserve (HRR): 180 – 60 = 120 BPM.
- Target Heart Rate (Zone 2 – 60%): (120 * 0.60) + 60 = 132 BPM.
How to Measure Your Resting Heart Rate
For the most accurate results, measure your resting heart rate first thing in the morning before getting out of bed. Place two fingers on your wrist (radial pulse) or neck (carotid pulse), count the beats for 60 seconds, or count for 15 seconds and multiply by four. Consistent tracking over 3-5 days will give you a reliable average to use in the calculator above.