TDEE & BMR Calculator

BMR (basal metabolic rate) is the energy your body burns at complete rest to keep breathing, circulating blood and holding its temperature. TDEE (total daily energy expenditure) is BMR multiplied by an activity factor, the calories you actually burn in a day. This calculator uses the Mifflin-St Jeor equation, the one most dietitians reach for: men BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5; for women the +5 becomes −161.

There are five activity levels with multipliers of 1.2 (sedentary), 1.375 (exercise 1–3 days a week), 1.55 (3–5 days), 1.725 (6–7 days) and 1.9 (athlete or physical job). A 25-year-old man at 175 cm and 70 kg has a BMR of about 1,674 kcal and a TDEE of about 2,594 kcal when moderately active; a 30-year-old woman at 160 cm and 55 kg has a BMR of about 1,239 kcal and a TDEE of about 1,704 kcal when lightly active.

Pick a goal to get a daily calorie target and macro split. Maintain uses your TDEE (25% protein, 45% carbs, 30% fat). Fat loss subtracts 15% and raises protein to 35% (40% carbs, 25% fat). Muscle gain adds 10% (30% protein, 50% carbs, 20% fat). Grams are converted at 4 kcal per gram of protein or carbs and 9 kcal per gram of fat, so the man above aiming for fat loss gets roughly 2,205 kcal and 193 g of protein.

BMI is shown too, using Taiwan’s Health Promotion Administration cut-offs: under 18.5 underweight, 18.5–24 normal, 24–27 overweight and 27 or more obese. The WHO international cut-offs for overweight and obesity are 25 and 30, so expect a stricter label here. Inputs are metric only (cm and kg). Every formula is a population average; muscle mass, body fat and health conditions all shift the real number, so talk to a doctor or dietitian before major diet changes, especially if you are pregnant or managing a condition.