Estimate your Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation.
A calorie calculator estimates how many calories you need per day based on your age, sex, weight, height, and activity level using the Mifflin-St Jeor equation.
To lose weight, eat 300-500 calories below your TDEE. To gain weight, eat 300-500 above. A deficit of 3,500 calories equals approximately 1 pound of body fat.