Question: how to calculate calories given carbs protein and fat?
Answer: To calculate the amounts in grams, you divide by how many calories there are per gram in each macronutrient (4 calories/g in protein, 4 calories/g in carbs and 9 calories/g in fat). For a 2.000 calories diet, your daily amounts would be: 800 calories from protein / 4 = 200 g Protein.