Calorie Calculator

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body uses in a day. It is estimated by first calculating your Basal Metabolic Rate (the calories burned at rest) using an equation such as Mifflin-St Jeor, then multiplying by an activity factor that reflects how active you are. The calculator combines your age, sex, height, weight, and activity level to produce this figure, which is the foundation for any plan to lose, maintain, or gain weight.

To lose weight you need a calorie deficit — eating fewer calories than your TDEE. A common, sustainable target is a deficit of about 500 calories per day, which tends to produce roughly half a kilogram (about one pound) of fat loss per week. Larger deficits speed up loss but are harder to maintain and can cost muscle and energy. The calculator gives your maintenance TDEE so you can subtract a sensible deficit to find a realistic daily target.

To gain weight you need a calorie surplus — eating more than your TDEE — combined with resistance training if your goal is muscle rather than fat. A moderate surplus of a few hundred calories a day supports lean gains while limiting excess fat. Adequate protein and progressive strength training are essential for turning extra calories into muscle. Use your TDEE as the baseline and add a controlled surplus on top.

Calorie needs depend on body size, sex, age, muscle mass, and activity level. Larger and more muscular bodies burn more at rest, men generally have higher needs than women of the same weight due to body composition, and needs tend to fall with age. Activity is often the biggest variable — a very active person can need hundreds or thousands more calories than a sedentary one of identical size. That is why the calculator asks for several inputs rather than giving a single universal number.

No. The equations used are well-validated averages, but individual metabolism varies, and self-reported activity levels are easy to over- or under-estimate. Treat the result as a well-informed starting point. Track your weight over a couple of weeks and adjust your intake up or down based on the actual trend rather than assuming the first estimate is perfect.