The amount of food to feed a dog varies depending on the dog's age, activity level, size and type of food. Puppies typically require more food than adult dogs because of the amount of calories they burn. Commercial dog food includes basic feeding guidelines on the packaging.
Larger dogs generally require less food per pound of body weight than small dogs if comparable in health and age. An overly active dog typically requires more food but should not be fed before or immediately after strenuous exercise due to potential digestive problems. Dogs with reduced energy levels, such as senior dogs, require less food, as they burn fewer calories and require fewer nutrients.