Cutting & Bulking Calculator

The cutting and bulking calculator turns a supplied total daily energy expenditure, or TDEE, into a calorie target and a complete macronutrient split. Goal is the central switch. Cutting uses 78 percent of TDEE, bulking uses 112 percent, and maintenance keeps TDEE unchanged. The estimated weekly scale change comes from the resulting daily deficit or surplus multiplied across seven days and divided by 3,500 calories per pound. That is a mathematical energy estimate, not a guarantee of tissue change. Protein is based on total body weight rather than lean mass: one gram per pound for cutting, 0.82 gram per pound for bulking, and 0.9 gram per pound for maintenance.

Fat receives 28 percent of calories while cutting and 25 percent otherwise. Carbohydrate fills the calories remaining after protein and fat, with a floor of zero. TDEE therefore has the largest direct effect on the calorie target, while body weight strongly affects protein and the carbohydrate remainder. Body-fat percentage is used only to report lean mass in kilograms; it does not alter the prescribed calories or macros. The model omits adaptive metabolism, changing water and glycogen, training volume, dietary adherence, and differences between gained or lost fat and lean tissue. Recalculate when the underlying TDEE or weight estimate changes.