BMR & TDEE Kalkylator

The BMR & TDEE calculator uses the Mifflin-St Jeor equation — the most clinically validated formula for estimating resting metabolic rate in most healthy adults (Frankenfield et al., 2005, Journal of the American Dietetic Association). Unlike older calculators using Harris-Benedict (1919), Mifflin-St Jeor consistently shows ±10% accuracy across diverse adult populations. Understanding your numbers is the first step to any evidence-based nutrition strategy.

BMR is what your body burns just to stay alive — breathing, circulation, thermoregulation, and cell repair. TDEE adds activity on top: a sedentary desk worker multiplies BMR by 1.2; an athlete training twice daily multiplies by up to 1.9. The 500 kcal deficit rule for weight loss comes from the approximation that 1 pound of fat ≈ 3,500 kcal, producing roughly 0.45 kg/week of loss. Surplus of 500 kcal/day should theoretically produce the same gain.

The macro breakdown (30% protein / 40% carbs / 30% fat) is a general-purpose starting point. Higher protein ratios (35-40%) are well-supported for muscle preservation during caloric restriction. Use these numbers as a starting point for 2-4 weeks, then adjust based on real-world outcomes. Always consult a registered dietitian for clinical-grade guidance. Use alongside our BMI Calculator and Water Intake Calculator for a complete health picture.