BMR Calculator
Calculate Basal Metabolic Rate - calories burned at rest.
Physical Information
Formula Selection
Your BMR
Calories burned at rest per day
Metabolism Type
Based on age and gender norms
Metabolic Age
Estimated metabolic age
Age Adjustment
Calories lost due to age
Daily Calorie Needs by Activity Level
How it works
Basal Metabolic Rate is the number of calories your body burns at complete rest just to stay alive — breathing, circulation, cell repair. It's the floor of your daily calorie needs. This calculator uses the Mifflin-St Jeor equation, the most accurate modern formula, which factors in weight, height, age, and sex.
Mifflin-St Jeor BMR (metric)
Men: BMR = 10·kg + 6.25·cm − 5·age + 5 Women: BMR = 10·kg + 6.25·cm − 5·age − 161
- kg
- body weight in kilograms
- cm
- height in centimetres
- age
- age in years
Worked example
- Man, 30 years old
- Weight = 80 kg, height = 180 cm
- BMR = 10×80 + 6.25×180 − 5×30 + 5
- BMR = 800 + 1,125 − 150 + 5
BMR ≈ 1,780 calories/day at rest.
Good to know
- BMR isn't your daily need — multiply it by an activity factor (1.2 sedentary to 1.9 very active) to get TDEE, the calories you actually burn.
- BMR falls with age and with lost muscle, which is why maintaining muscle helps keep metabolism up.
- It's an estimate: real metabolism varies with genetics, hormones, and body composition, so use the number as a starting point and adjust to results.
Related Calculators
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR is calories burned at complete rest. TDEE (Total Daily Energy Expenditure) is BMR plus activity calories - your actual daily burn.
How accurate are BMR calculations?
Formulas estimate within 10% accuracy for most people. Actual BMR varies based on genetics, muscle mass, and metabolic health.
How can I increase my BMR?
Build muscle through strength training, maintain adequate protein intake, get enough sleep, and avoid extreme calorie restriction which lowers metabolism.
How often should I exercise?
The WHO recommends at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity per week.
What is a balanced diet?
A balanced diet includes variety from all food groups: fruits, vegetables, whole grains, lean proteins, and healthy fats.
How much water should I drink?
General recommendation is 8-10 glasses (2-2.5 liters) per day, adjusted for activity level and climate.
How important is sleep?
Sleep is crucial for physical recovery, mental health, and overall wellbeing. Adults need 7-9 hours nightly.