Target Heart Rate Zone Calculator
Age must be greater than 19.
Age must be less than 120.
Heart Rate Calculator: Understanding Your Training Zones
This calculator helps determine your maximum heart rate (MHR) and your exercise target heart rate (THR) zones measured in beats per minute (bpm). For adults over 19 years old, target heart rate zones can be calculated using three different methods.
Maximum Heart Rate Formula
MHR = 220 – Age
Basic Formula (Age-Based)
THR = MHR × %Intensity
Karvonen Formula
THR = [(MHR – RHR) × %Intensity] + RHR
Target Heart Rate Calculation Methods
1. Basic Formula (Age-Based)
THR = MHR × %Intensity
- This traditional method used by the American Heart Association calculates THR by multiplying your maximum heart rate by your desired intensity percentage.
- Example: At 70% intensity, THR = MHR × 0.70
2. Karvonen Formula with Age & RHR
THR = [(MHR – RHR) × %Intensity] + RHR
- Calculates MHR based on your age while incorporating your measured resting heart rate
- Example: At 70% intensity, THR = ((MHR – RHR) × 0.70) + RHR
3. Karvonen Formula with Measured MHR & RHR
THR = [(MHR – RHR) × %Intensity] + RHR
- Uses your actual measured maximum and resting heart rates for greatest accuracy
- Example: At 50% intensity, THR = ((MHR – RHR) × 0.50) + RHR
- The difference between MHR and RHR is called your Heart Rate Reserve (HRR)
Training Zones Chart
The American Heart Association recommends exercising at 50-85% of your MHR, with moderate activity at 50-70% and vigorous activity at 70-90%.
| Training Zone | Intensity (% of MHR) |
|---|---|
| Maximum (VO₂ Max Zone) | 90% – 100% |
| Hard (Anaerobic Zone) | 80% – 90% |
| Moderate (Aerobic Zone) | 70% – 80% |
| Light (Fat Burn Zone) | 60% – 70% |
| Very Light (Warm Up Zone) | 50% – 60% |
Each zone provides different training benefits, from improving recovery to building endurance and anaerobic capacity.