What is BMR?
Your Basal Metabolic Rate (BMR) is the number of calories your body needs at rest to maintain vital functions. This calculator estimates your BMR using the Mifflin-St Jeor, Harris-Benedict, or Katch-McArdle formulas. BMR is the foundation for calculating your daily calorie needs.
BMR Formulas
- Mifflin-St Jeor: For men: BMR = 10W + 6.25H - 5A + 5; For women: BMR = 10W + 6.25H - 5A - 161
- Harris-Benedict (revised): For men: BMR = 13.397W + 4.799H - 5.677A + 88.362; For women: BMR = 9.247W + 3.098H - 4.330A + 447.593
- Katch-McArdle: BMR = 370 + 21.6 × (1 - F) × W (W = weight in kg, F = body fat % as decimal)
Daily Calorie Needs by Activity Level
- Sedentary: BMR × 1.2 (little or no exercise)
- Light: BMR × 1.375 (exercise 1-3 days/week)
- Moderate: BMR × 1.55 (exercise 3-5 days/week)
- Active: BMR × 1.725 (hard exercise 6-7 days/week)
- Very Active: BMR × 1.9 (physical job or intense training)