How Much Formula or Milk Does My Baby Need?
The answer depends on age and size. In general, a newborn will only take 10-15ml (1/3-1/2 ounce) every 2-4 hours for the first few days. After a few days of age, then they will usually take about 1-2 ounces a feeding. They need to eat every 2-4 hours until they regain their birth weight. They are expected to do this by 14 days of age.
I do not recommend feeding more than 2 ounces a feeding until about 2 months of age, more than 4 ounces per feeding until 4 months of age. After that, they can take up to 6-8 ounces a feeding. They need formula or breast milk, a minimum of 24 ounces a day, maximum of 32 ounces a day-for all ages.
Babies should only drink breast milk or formula, from birth to 6 months of age. Nothing else.
At 6 months of age, they can have up to 6 ounces of juice a day, after they get their 24-32 ounces of milk or formula. Only then, if they are still thirsty, should they be given water.
At 1 year of age, they should have whole milk (not 1%, 2%, skim, almond milk, rice milk, etc.) until they are 2 years old, in order to get the recommended amount of fat and calories in their diet. After 2 years of age, they can drink whatever milk the family drinks. Note: The AAP recommends whole milk until 3 years of age. There is no recommendation for formula beyond the first birthday, but breast feeding can be continued.
These are general rules and there are exceptions based on individual circumstances, etc.