BMI & TDEE Calculator
Your body mass index plus daily calorie needs — for fat loss, maintenance, or lean muscle gain.
Private by design: everything runs in your browser. Nothing is uploaded.
How it works
- Enter your weight, height, age and activity level (metric or imperial units).
- Hit Calculate to get your BMI category and daily calorie needs.
- Use the calorie targets as a starting point for fat loss, maintenance, or muscle gain.
FAQ
What formula does this use?
Resting metabolism uses the Mifflin-St Jeor equation, the most widely used estimate, multiplied by a standard activity factor to get TDEE (total daily energy expenditure).
What are the BMI categories?
Underweight below 18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese 30 and above.
How fast will I lose weight on the fat-loss target?
The fat-loss target subtracts 500 kcal/day from your TDEE, which typically means about 0.5 kg (1 lb) per week for most adults.