Basal Metabolic Rate (BMR) represents the minimum amount of energy your body needs to sustain life. It is the calories required for basic physiological functions like heartbeat, breathing, temperature regulation, and cell regeneration.
This calculator supports the Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle formulas. The Harris-Benedict formula is Male: 66 + (13.7 Γ weight kg) + (5 Γ height cm) - (6.8 Γ age); Female: 655 + (9.6 Γ weight kg) + (1.8 Γ height cm) - (4.7 Γ age). Developed in 1919 and revised in 1984, it remains a medical standard with approximately 90% accuracy.
Total Daily Energy Expenditure represents your total calorie burn. Multiply BMR by activity level: Sedentary (0-1Γ/week): BMR Γ 1.2, Light (1-3Γ/week): BMR Γ 1.375, Moderate (3-5Γ/week): BMR Γ 1.55, Active (6-7Γ/week): BMR Γ 1.725, Very Active (2Γ/day): BMR Γ 1.9.
Weight Loss: TDEE - 500kcal (~0.5kg/week). Maintenance: TDEE. Weight Gain: TDEE + 500kcal (~0.5kg/week). Combine with adequate protein (1.6-2.2g/kg) and resistance training for best results.
Age: BMR decreases 2-3% per decade after age 20 due to muscle loss. Gender: Men typically have 5-10% higher BMR than women due to greater muscle mass and lower body fat percentage.
Resistance training builds muscle for higher resting calorie burn; high-protein intake has a high thermic effect; adequate sleep prevents hormonal imbalances; staying hydrated with 2L+ water daily helps; and HIIT training elevates metabolism for 24+ hours.