Male
Female
Used for Maximum Heart Rate estimation logic.
Enter for higher accuracy (Karvonen Method). Leave blank for Standard Method.
Your Target Fat Burning Zone
Zone Range (60% – 70%):
Estimated Max Heart Rate:
Calculation Method:
Maintain this heart rate during exercise for optimal fat oxidation.
What is the "Fat Burning Zone"?
The "fat burning zone" refers to a specific physiological intensity where your body prioritizes burning stored fat for fuel over carbohydrates. This typically occurs at a lower intensity compared to high-performance cardio training.
Physiologically, when your heart rate is between 60% and 70% of your maximum capacity, your body has enough oxygen available to oxidize fat efficiently. At higher intensities (above 75-80%), your body switches to glycogen (carbs) because it needs faster energy than fat metabolism can provide.
How This Calculator Works
This tool uses two primary methods to determine your optimal heart rate:
Standard Method (MHR): Estimates your Maximum Heart Rate (MHR) based on age and sex, then calculates 60-70% of that number. This is useful for beginners.
Karvonen Formula (HRR): If you provide your Resting Heart Rate (RHR), the calculator uses the Heart Rate Reserve method. This is significantly more accurate because it factors in your current fitness level.
The Formulas
Step 1: Estimate Maximum Heart Rate (MHR)
Male: 220 - Age
Female: 226 - Age