HOW MUCH FORMULA DOES MY BABY NEED?
As you develop a bottle-feeding routine for you and your baby, the two of you will work out which formula is best, how much, and how often. This routine may change as your baby grows. As a general guide:
Between birth and six months of age your baby will need an average of 2 to 2.5 ounces of formula per pound per day. So, a baby that weighs ten pounds, will need approximately 20 to 25 ounces per day.
Small, more frequent feedings will work better than larger ones spaced farther apart. Your baby's tummy is about the size of his fist. Take a full bottle and place it next to your baby's fist and you'll see why tiny tummies often spit the milk back up when they're given too much at one time.