Fitness
BMR Calculator
Calculate your Basal Metabolic Rate (BMR) using Mifflin-St Jeor, Revised Harris-Benedict, and Katch-McArdle formulas.
FAQs
What is Basal Metabolic Rate (BMR)?
BMR is the minimum number of calories your body needs to maintain basic life-sustaining functions (like breathing and circulation) at complete rest.
Which BMR formula is the most accurate?
The Mifflin-St Jeor equation is widely considered the most accurate for modern lifestyles. If you know your body fat percentage, the Katch-McArdle formula is highly recommended as it accounts for lean muscle mass.
What is the difference between BMR and RMR?
BMR (Basal Metabolic Rate) is measured under strict laboratory conditions at rest. RMR (Resting Metabolic Rate) is measured under less restrictive conditions and is slightly higher but close enough for daily planning.
How does BMR help with weight loss?
Your BMR is the foundation of your daily calorie expenditure. By adding your activity level, you get your Total Daily Energy Expenditure (TDEE). Eating below your TDEE creates a calorie deficit for weight loss.
How to Use the BMR Calculator
Estimate your Basal Metabolic Rate — the calories your body burns at complete rest.
- Enter your age, sex, height, and weight.
- See your BMR in calories per day.
- Multiply by an activity factor to get total daily needs (TDEE).
BMR Formula (Mifflin-St Jeor)
Men
The most widely used modern BMR estimate.
Example:
Input: 80kg, 180cm, 30y
Calculation: 800 + 1125 − 150 + 5
Result: 1,780 kcal/day
Women
Same formula with a different constant.
Example:
Input: 65kg, 165cm, 30y
Calculation: 650 + 1031 − 150 − 161
Result: 1,370 kcal/day
Real-World Use Cases
Calorie Targets
Set a baseline before adding activity.
Weight Management
Eat below TDEE to lose, above to gain.
Tips
Tips
- BMR is rest-only; TDEE adds activity.
- Muscle mass raises BMR, which is why strength training helps.