🔥 BMR Calculator
Calculate your Basal Metabolic Rate (BMR) - the number of calories your body burns at complete rest. Get personalized daily calorie needs by activity level and weight management targets. Uses the accurate Mifflin-St Jeor equation for precise results.
Avg Male BMR
1,660 kcal
Avg Female BMR
1,400 kcal
Muscle Impact
+15%
Age Factor
-2%/year
Enter Your Details
Using Mifflin-St Jeor Equation - Most accurate for general population
Your Results
Mifflin-St Jeor EquationBasal Metabolic Rate
Your body burns this at complete rest
Daily Calorie Needs by Activity
Little or no exercise
1,992 kcal
1-3 days/week
2,283 kcal
3-5 days/week
2,573 kcal
6-7 days/week
2,864 kcal
Physical job + intense exercise
3,154 kcal
Weight Management Targets
Mild Weight Loss
2,323
(250-300g/week)
Weight Loss
2,073
(500g/week)
Extreme Loss
1,573
(1kg/week - caution)
BMR Breakdown
- Brain ~20%
- Liver ~25%
- Heart & Lungs ~15%
- Muscles ~25%
Boost Your BMR
- Build muscle mass
- Eat enough protein
- Stay hydrated
- Get quality sleep
- Eat small, frequent meals
What is BMR?
Your Basal Metabolic Rate is the number of calories your body burns at complete rest to maintain vital functions like breathing, circulation, and cell production. It accounts for 60-75% of total daily calorie burn.
The Mifflin-St Jeor Equation
Men: BMR = 10W + 6.25H - 5A + 5
Women: BMR = 10W + 6.25H - 5A - 161
Where W=weight(kg), H=height(cm), A=age(years)
Most accurate for general population (90% accuracy)
Why Does It Matter?
Knowing your BMR is the first step in weight management. It helps you understand your baseline calorie needs before factoring in physical activity, allowing for precise calorie targets for weight loss, gain, or maintenance.
Frequently Asked Questions About BMR
What is BMR and how is it different from TDEE?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest for basic life functions.
TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through physical activity, NEAT (Non-Exercise Activity Thermogenesis), and TEF (Thermic Effect of Food - digestion).
Our calculator shows both - BMR and TDEE for different activity levels.
How accurate is BMR calculation?
The Mifflin-St Jeor equation is considered the most accurate for the general population, with about 90% accuracy within ±10% of actual BMR.
Factors affecting accuracy: body composition (muscle vs fat ratio), genetics, hormonal factors, and recent dieting history.
For precise measurement, indirect calorimetry in a clinical setting is required.
Does muscle mass affect BMR?
Yes, significantly! Muscle tissue burns 6-7 calories per pound per day, while fat burns only 2-3 calories.
Adding 5kg of muscle can increase BMR by ~70-100 calories/day. This is why strength training is crucial for long-term weight management.
How does age affect BMR?
BMR typically decreases by 1-2% per decade after age 20 due to loss of muscle mass.
For a person with BMR of 1500 at age 20:
- At 40: ~1,440-1,470 kcal
- At 60: ~1,380-1,440 kcal
Regular exercise and maintaining muscle can significantly slow this decline.
Should I eat below my BMR to lose weight?
No! Never eat below your BMR for extended periods.
Eating below BMR can slow metabolism, lead to muscle loss, cause nutritional deficiencies, and result in weight regain later.
Instead, create a deficit from your TDEE (Total Daily Energy Expenditure):
- Safe deficit: 300-500 calories below TDEE
- Weight loss: 0.5-1 kg per week
- Minimum calories: 1,500 (men) / 1,200 (women)
Understanding Your BMR Results
What Affects Your BMR
- Muscle Mass↑ Increases
- Age↓ Decreases
- Height↑ Increases
- Weight↑ Increases
- GeneticsVariable
Sample Meal Distribution (2,000 kcal)
- Breakfast400-500 kcal
- Lunch500-600 kcal
- Dinner500-600 kcal
- Snacks200-300 kcal