BMR Calculator
Calculate your Basal Metabolic Rate (BMR) - the number of calories your body burns at rest. Essential for weight management and determining daily calorie needs.
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BMR Results
Formula Comparison
Daily Calorie Needs (TDEE)
Use our Calorie Calculator for detailed TDEE calculations.
BMR Formula Explanations
Mifflin-St Jeor Equation
Most accurate formula for the general population. Developed in 1990 and widely used by nutritionists and dietitians.
Men: 10 × weight(kg) + 6.25 × height(cm) - 5 × age + 5
Women: 10 × weight(kg) + 6.25 × height(cm) - 5 × age - 161
Harris-Benedict Equation
Original formula from 1919, revised in 1984. Still widely used but less accurate than Mifflin-St Jeor for modern populations.
Men: 88.362 + 13.397 × weight(kg) + 4.799 × height(cm) - 5.677 × age
Women: 447.593 + 9.247 × weight(kg) + 3.098 × height(cm) - 4.330 × age
Katch-McArdle Equation
Most accurate for lean individuals or those who know their body fat percentage. Based on lean body mass.
Formula: 370 + 21.6 × LBM(kg)
LBM: Lean Body Mass = Weight × (100 - Body Fat%) ÷ 100
Understanding Your BMR
What is BMR?
Basal Metabolic Rate (BMR) represents the minimum amount of energy your body needs to maintain basic physiological functions while at rest.
- • Breathing and circulation
- • Cell production and repair
- • Protein synthesis
- • Brain and nerve function
- • Temperature regulation
BMR vs TDEE
BMR is your baseline calorie burn at rest. Total Daily Energy Expenditure (TDEE) includes all activities.
TDEE = BMR × Activity Factor
• BMR: ~60-75% of total calories
• Physical Activity: ~15-30%
• Thermic Effect of Food: ~8-10%
Factors Affecting BMR
- • Age: BMR decreases ~1-2% per decade after age 20
- • Gender: Men typically have higher BMR than women
- • Body Size: Larger bodies burn more calories
- • Muscle Mass: Muscle tissue burns more calories than fat
- • Genetics: Can vary BMR by up to 20%
- • Hormones: Thyroid function significantly affects BMR
Using Your BMR
- • Weight Loss: Eat above BMR but below TDEE
- • Weight Gain: Eat above TDEE with strength training
- • Maintenance: Match calorie intake to TDEE
- • Never eat below BMR for extended periods
- • Use BMR to set realistic calorie goals
Boosting Your Metabolism
Build Muscle Mass
Muscle tissue burns more calories at rest than fat tissue. Strength training can help maintain and build muscle, especially important as you age.
Stay Active
Regular physical activity not only burns calories during exercise but can increase your metabolic rate for hours afterward (EPOC effect).
Eat Enough Protein
Protein has a higher thermic effect than carbs or fats, meaning your body burns more calories digesting and processing protein-rich foods.
Don't Crash Diet
Severe calorie restriction can lower your BMR as your body adapts to conserve energy. Aim for moderate deficits and include strength training.
Get Quality Sleep
Poor sleep can affect hormones that regulate hunger and metabolism. Aim for 7-9 hours of quality sleep per night for optimal metabolic health.
Stay Hydrated
Proper hydration supports all metabolic processes. Even mild dehydration can slightly decrease your metabolic rate and energy levels.
Related Calculators
Calorie Calculator
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Body Fat Calculator
Calculate body fat percentage
Macro Calculator
Calculate macronutrient needs