Calories set the overall energy budget, but how you split it between protein, carbohydrate, and fat shapes hunger, muscle retention, and how an eating style actually feels day to day. This calculator converts a calorie target into grams for a few common approaches.
Each eating style divides total calories into a percentage of protein, carbs, and fat, which is then converted to grams using 4 calories per gram of protein and carbohydrate, and 9 calories per gram of fat. Balanced (40/30/30 carb/protein/fat) suits general health; high protein favours muscle retention; low carb and keto shift the bulk of calories toward fat instead.