Basal Metabolic Rate Calculator (BMR)
This calculator estimates your basal metabolic rate, the number of calories your body burns at complete rest just to keep vital functions running, such as breathing, circulation, and cell repair. Enter your sex, weight, height, and age to get your BMR in kcal per day, plus your estimated total daily energy expenditure across five activity levels, from sedentary to very active. It is a practical starting point for planning nutrition, weight loss, or muscle gain.
Your basal metabolic rate
kcal/day
Calorie expenditure by activity level
The basal metabolic rate is estimated with the Mifflin-St Jeor equation. It is a statistical approximation: actual expenditure varies with body composition, genetics, and health status. It is not a substitute for professional assessment.
Publicidad
How it works
The result uses the Mifflin-St Jeor equation, considered the most reliable formula for estimating resting metabolism in the general population. It computes a base value of 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years), then adds 5 for men or subtracts 161 for women. That figure is your BMR: the energy needed at total rest. To estimate your total daily energy expenditure (TDEE), the calculator multiplies your BMR by an activity factor between 1.2 (sedentary) and 1.9 (very active). BMR is only the baseline, while TDEE reflects everything you actually burn in a day, including movement, exercise, and digestion.
Publicidad
Preguntas frecuentes
- What is the basal metabolic rate (BMR)?
- Your BMR is the amount of energy, measured in calories, that your body needs at complete rest to keep essential functions running: breathing, blood circulation, body temperature, brain activity, and cell repair. It represents the largest share of your daily calorie needs, typically 60 to 70 percent, before you add any movement or exercise.
- What is the difference between BMR and TDEE?
- BMR is the calories you burn at total rest, doing nothing at all. TDEE (total daily energy expenditure) is everything you burn in a full day, including walking, working, exercising, and digesting food. TDEE is calculated by multiplying your BMR by an activity factor, so it is always higher than your BMR. For weight management, TDEE is the number you compare your calorie intake against.
- How is the BMR calculated?
- This calculator uses the Mifflin-St Jeor equation: 10 × weight in kg + 6.25 × height in cm − 5 × age in years, then + 5 for men or − 161 for women. Published in 1990, it is regarded as more accurate than older formulas like Harris-Benedict for most people.
- What is the BMR used for?
- Knowing your BMR and TDEE lets you set a realistic calorie target. To lose weight you eat below your TDEE, to gain weight or muscle you eat above it, and to maintain your weight you match it. It is also useful for understanding why calorie needs differ between people of different size, age, and sex.
- How accurate is this estimate?
- The Mifflin-St Jeor equation predicts BMR within about 10 percent for most healthy adults, but it does not account for muscle mass, body fat percentage, or medical conditions. Athletes with high muscle mass may burn more, and the estimate is a guide rather than a precise measurement. For clinical precision, indirect calorimetry is required.