It can be very difficult to understand how much a baby should eat at what time. By three months most babies are on a good feeding schedule, and usually they can go between three and four hours between meals. Some parents are breastfeeding, and they breastfeed on demand, which means whenever they believe the baby is hungry, they give the baby a meal. Traditionally, however, parents do some sort of scheduled feeding. But how much they are fed is really dependant on your particular baby. At three months, one baby may take three ounces, and another particularly hungry baby may take six ounces. It's really about: Are they satiated after the meal? Do they finish their bottle? Can they last three hours comfortably, four hours to the next feeding? By logging all of their feedings and the amounts that they're having per day you can really judge if the baby is getting enough formula. If you notice that your baby is not gaining weight, not taking their feeds, that's something that you really need to speak to your doctor about. But generally between three and six ounces every three to four hours is roughly what a baby, after three months of age, should be eating. And by logging the baby, and understanding what their rhythms are, you can get into a wonderful feeding schedule for the rest of their infancy.