Dry Food

• 1). Weigh your cat.
  
  
• 2). Calculate the number of calories your cat needs by multiplying his weight in pounds by 30.
  
  Dry cat food has an average of 300 calories per cup, according to TalkToTheVet.com. At 30 calories per pound, an 8-pound cat needs 240 calories per day (8 x 30 = 240), which equals 4/5 cup of dry food.
  
  
• 3). Measure 4/5 cup of dry cat food in a measuring cup and pour it in your cat's bowl. This amount is enough to feed your cat for one day.
  
  

Canned Food

• 1). Weigh your cat.
  
  
• 2). Calculate the number of calories your cat needs by multiplying her weight in pounds by 30.
  
  On average, canned cat food contains 200 calories per 6 1/2-ounce can, according to TalkToTheVet.com. An 8-pound cat should have 240 calories per day, which is equal to 1 1/5 cans per day.
  
  
• 3). Scoop one can of cat food and 1/5 of a second can of cat food into your cat's bowl each day. If desired, divide this amount into two feedings per day.