Basal Metabolic Rate (BMR) Calculator
Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at rest. Use this calculator to estimate your BMR based on factors like age, gender, weight, and height.
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Frequently asked questions
BMR is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation, heart rate, and cell production. It represents the minimum energy needed to keep your body functioning if you were to rest all day.
Our calculator uses scientifically validated formulas (Mifflin-St Jeor, Harris-Benedict, Katch-McArdle) with accuracy within 10-15% for most people. The Mifflin-St Jeor formula is considered the most accurate for general population. Individual variations in metabolism, muscle mass, genetics, and health conditions can affect actual BMR.
Mifflin-St Jeor (default) is recommended for most people as it's the most accurate modern formula. Harris-Benedict is an older but still reliable alternative. Katch-McArdle is best if you know your body fat percentage, as it accounts for lean muscle mass and provides more personalized results for athletic individuals.
BMR is the calories burned at complete rest. TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through daily activities, exercise, and digestion. To lose, maintain, or gain weight, you need to know your TDEE, not just BMR. Use our TDEE calculator to find your total daily calorie needs.
Build muscle mass through strength training, as muscle burns more calories at rest than fat. Stay hydrated, get 7-9 hours of quality sleep, eat enough protein (supports muscle maintenance), avoid crash diets that slow metabolism, and consider high-intensity interval training (HIIT) which can boost metabolism for hours after exercise.
Yes, BMR typically decreases with age due to loss of muscle mass and hormonal changes. On average, BMR decreases by about 1-2% per decade after age 20. This is why maintaining muscle mass through resistance training becomes increasingly important as we age.
Men typically have higher BMR than women because they generally have more muscle mass and less body fat. Muscle tissue burns more calories at rest than fat tissue. Hormonal differences also play a role in metabolic rate differences between genders.
No, you should not eat below your BMR. Eating significantly below BMR can slow your metabolism, cause muscle loss, and trigger hormonal imbalances. Instead, calculate your TDEE and create a moderate calorie deficit (10-20% below TDEE) for sustainable, healthy weight loss.