How to Calculate TDEE and Your Daily Calories
Learn what TDEE and BMR mean, how the Mifflin-St Jeor formula works, and how to turn the number into a calorie target for losing, holding, or gaining weight.
Quick Answer
TDEE is the total number of calories your body burns in a day. It is your Basal Metabolic Rate, the energy you use at complete rest, multiplied by an activity factor between 1.2 and 1.9. This calculator estimates BMR with the Mifflin-St Jeor equation from your sex, age, height, and weight, scales it by your activity level, and then gives you concrete calorie targets: eat below the maintenance number to lose weight, above it to gain. About 7,700 calories equals a kilogram, so a 550 calorie daily gap moves roughly half a kilogram a week.
Try The TDEE Calculator →How TDEE Works
Your daily burn comes in two parts. The first and largest is BMR, the energy your body spends just staying alive: keeping your heart beating, your lungs working, and your temperature steady. For most people that is 60 to 70 percent of the total. The second part is everything you do on top of that, from walking and typing to formal exercise. TDEE combines the two by taking your BMR and multiplying it by a single activity factor, a shortcut that captures how much your movement adds to the resting figure. A sedentary person uses a factor of 1.2, while someone training hard most days uses up to 1.9.
The Mifflin-St Jeor Formula
BMR here is estimated with the Mifflin-St Jeor equation, considered one of the most accurate for the general population. For men it is 10 times weight in kilograms, plus 6.25 times height in centimetres, minus 5 times age in years, plus 5. For women the final term is minus 161 instead of plus 5. A 30-year-old man of 70 kg and 175 cm has a BMR of about 1,649 calories, and at a moderate activity level his TDEE is roughly 2,556. If you enter imperial units, the calculator converts pounds and inches first, so the result is the same either way.
Turning TDEE Into a Calorie Goal
Weight change is mostly about the gap between what you eat and what you burn. Because a kilogram of body weight holds about 7,700 calories, a daily deficit of 550 calories predicts around half a kilogram of loss a week, and the same surplus predicts a similar gain. The tool lays out these targets for you: a gentle loss, a steady loss, maintenance, and a gain. It floors any loss target at your BMR, because eating below your resting requirement for long is neither comfortable nor wise.