High caloric density foods pack more energy into smaller portions, which suits active, working, or underweight animals. Low caloric density foods provide larger, more satisfying meals with fewer calories, helping overweight pets feel full during weight-loss programs. Kibble typically ranges from 300-500 kcal per cup, while wet food may provide 200-400 kcal per can depending on formulation. Always check the calorie content statement on the label (listed as kcal/kg and often kcal/cup or kcal/can) and measure portions with a kitchen scale or measuring cup. Feeding guides on packaging are starting points; adjust based on your pet's body condition score, activity level, and veterinary recommendations.