Calculate Your Basal Metabolic Rate
Calories per day at rest
Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation, and cell production. It represents 60-75% of your total daily calorie expenditure and is influenced by age, gender, body composition, and genetics.
This calculator uses the Mifflin-St Jeor equation, considered the most accurate for general populations:
BMR is the foundation for calculating your Total Daily Energy Expenditure (TDEE). To determine your actual calorie needs, multiply your BMR by an activity factor (1.2 for sedentary to 1.9 for very active). Use BMR to set calorie targets for weight loss, maintenance, or muscle gain.
BMR is calories burned at complete rest, while TDEE (Total Daily Energy Expenditure) includes all activities. TDEE = BMR × activity multiplier. For example, if your BMR is 1,500 and you're moderately active, your TDEE = 1,500 × 1.55 = 2,325 calories.
The Mifflin-St Jeor equation (used in this calculator) is considered most accurate for the general population with about 90% accuracy. The Katch-McArdle formula is more accurate if you know your body fat percentage, as it accounts for lean body mass.
Yes! Building muscle through strength training is the most effective way to increase BMR since muscle tissue burns more calories at rest than fat. Other factors include eating enough protein, staying hydrated, getting adequate sleep, and avoiding extreme calorie restriction which can lower BMR.
Several factors can lower BMR: aging (2% decrease per decade after 30), prolonged calorie restriction, loss of muscle mass, hormonal imbalances (thyroid issues), or genetics. If concerned, consult a healthcare provider to rule out medical causes. Focus on building muscle and eating adequate calories to support a healthy metabolism.