BMR Calculator
Calculate Your BMR
Enter your measurements below to calculate your Basal Metabolic Rate and daily calorie needs.
What is BMR?
BMR (Basal Metabolic Rate) is the amount of energy your body needs to maintain basic physiological functions at rest, such as breathing, circulation, and cell production. It is the largest component of your daily calorie needs.
BMR Formulas
- Mifflin-St Jeor Equation (most accurate for most people):
For men: BMR = 10 × weight (kg) + 6.25 × height (cm) - 5 × age (y) + 5
For women: BMR = 10 × weight (kg) + 6.25 × height (cm) - 5 × age (y) - 161 - Revised Harris-Benedict Equation:
For men: BMR = 13.397 × weight (kg) + 4.799 × height (cm) - 5.677 × age (y) + 88.362
For women: BMR = 9.247 × weight (kg) + 3.098 × height (cm) - 4.330 × age (y) + 447.593 - Katch-McArdle Formula (uses lean body mass):
BMR = 370 + 21.6 × (1 - body fat %) × weight (kg)
Daily Calorie Needs Based on Activity Level
| Activity Level | Multiplier |
|---|---|
| Sedentary (little or no exercise) | 1.2 |
| Light exercise (1-3 days/week) | 1.375 |
| Moderate exercise (3-5 days/week) | 1.55 |
| Heavy exercise (6-7 days/week) | 1.725 |
| Very heavy exercise (physical job or 2x training) | 1.9 |
To estimate your daily calorie needs, multiply your BMR by the appropriate activity factor above.
Factors Affecting BMR
- Muscle mass: More muscle increases BMR.
- Age: BMR decreases with age.
- Genetics: Hereditary factors can affect BMR.
- Weather: Extreme temperatures can raise BMR.
- Diet: Starvation lowers BMR; frequent small meals may increase it.
- Pregnancy: Increases BMR.
- Supplements: Some drugs/supplements (e.g., caffeine) can raise BMR.