BMR Calculator - Calculate Your Basal Metabolic Rate

BMR (Basal Metabolic Rate) is the calories needed for basic bodily functions at rest, while TDEE (Total Daily Energy Expenditure) includes all daily activities. TDEE equals BMR multiplied by an activity factor. For example, if your BMR is 1,500 calories and you're moderately active, your TDEE would be approximately 1,500 × 1.55 = 2,325 calories.

Yes, several strategies can increase BMR: building muscle mass (muscle burns more calories than fat), regular exercise, adequate protein intake, staying hydrated, getting enough sleep, and managing stress. Age-related BMR decline can be slowed through strength training and maintaining muscle mass. However, the most significant factor is usually body composition changes.

Men typically have higher BMR due to greater muscle mass, higher testosterone levels, and different body composition. Muscle tissue requires more energy to maintain than fat tissue. On average, men have 10-15% higher BMR than women of similar age and weight. However, individual variations exist, and some women may have higher BMR than some men depending on muscle mass and other factors.

BMR calculators provide reasonable estimates but aren't perfectly accurate for individuals. The Mifflin-St Jeor equation is generally accurate within 10% for most people, but actual BMR can vary by 10-20% due to factors like genetics, hormonal differences, and body composition. For precision, consider professional metabolic testing using indirect calorimetry, which measures actual oxygen consumption and carbon dioxide production.

Yes, BMR decreases during weight loss due to reduced body mass and potential loss of muscle tissue. This creates a "starvation response" where metabolism slows to conserve energy. To minimize BMR reduction during weight loss, focus on preserving muscle mass through strength training and adequate protein intake. Sustainable weight loss should aim for 0.5-1 kg per week to avoid significant metabolic slowdown.

BMR naturally decreases with age, typically by 1-2% per decade after age 20. This decline is primarily due to loss of muscle mass (sarcopenia), hormonal changes, and reduced organ metabolic activity. Regular strength training and maintaining muscle mass can help slow this age-related BMR decline. Older adults may need fewer calories for weight maintenance but still require adequate nutrition for health.