A 3-day-old baby needs about 1 to 2 ounces (30 to 60 ml) of milk per feeding, eaten 8 to 12 times over 24 hours. That works out to roughly 15 to 20 ounces total per day, though the exact amount varies from baby to baby. These small volumes match the size of your newborn’s stomach, which at day 3 holds only about 22 to 27 ml at a time, roughly the size of a walnut or ping pong ball.
How Much Per Feeding at Day 3
The American Academy of Pediatrics recommends that babies in their first week eat no more than about 1 to 2 ounces (30 to 60 ml) per feeding. By the time a few weeks have passed, that amount climbs to 2 to 3 ounces per feeding. But at day 3, your baby’s stomach is still tiny and growing fast. On day one it held about the size of a cherry; by day 3 it has expanded to walnut size, but it still can’t handle large volumes.
If you’re breastfeeding, you won’t be measuring output the same way you would with a bottle, and that’s fine. Your body is transitioning from colostrum, the thick yellowish first milk, to what’s called transitional milk. This shift typically happens between days 2 and 5, and you may notice your breasts feeling fuller and warmer, with the milk gradually changing to a bluish-white color. Colostrum comes in very small amounts, but it’s nutrient-dense and calorie-rich, so even a few milliliters per feeding in the first couple of days is enough.
For formula-fed babies, the guideline is more straightforward: offer 1 to 2 ounces per bottle and let your baby tell you when they’re done. A general rule for formula intake is about 2.5 ounces per day for every pound of body weight. So an average 7.5-pound newborn would need roughly 18 to 19 ounces spread across the day. That said, babies regulate their own intake from feeding to feeding, so some sessions will be bigger than others.
How Often to Feed
At 3 days old, your baby will likely want to eat every 1 to 3 hours, which adds up to 8 to 12 feedings in a 24-hour period. Breastfed babies tend to eat on the higher end of that range because breast milk digests faster than formula. Formula-fed newborns typically eat every 2 to 3 hours.
Feeding on demand, rather than on a strict schedule, is important in the first week. Newborns go through periods of cluster feeding where they want the breast or bottle several times in quick succession, often in the evening. This is normal and helps signal your body to produce more milk if you’re breastfeeding. Don’t try to stretch intervals between feedings at this stage.
How to Tell Your Baby Is Hungry or Full
Crying is actually a late hunger signal. By the time a 3-day-old is wailing, they’ve been hungry for a while and may be too upset to latch or eat well. Earlier cues to watch for include putting hands to their mouth, turning their head toward your breast or the bottle (called rooting), puckering or smacking their lips, and clenching their fists.
When your baby is full, they’ll close their mouth, turn their head away from the breast or bottle, and visibly relax their hands. These signals are your best guide for knowing whether you’re offering enough milk. If your baby consistently falls asleep at the breast within a minute or two, that may mean they’re too sleepy to eat well rather than truly full, and it’s worth gently waking them to continue the feeding.
Weight Loss in the First Few Days
Almost all newborns lose weight after birth, and day 3 is typically when the loss peaks. Healthy, full-term, breastfed babies commonly lose 7% to 8% of their birth weight by day 3. Some lose 10% or more. For a baby born at 7.5 pounds, a 7% loss means dropping to about 7 pounds, which looks like a lot but is considered normal.
Babies generally start regaining weight once a mother’s milk fully comes in, usually between days 3 and 5. Most newborns return to their birth weight by 10 to 14 days. If your baby has lost more than 10% of birth weight by day 3 or hasn’t started gaining by day 5, your pediatrician will likely want to evaluate feeding and may suggest supplementation.
Signs Your Baby Is Getting Enough
Since you can’t measure exactly how much milk transfers during breastfeeding, output is the best proxy. By day 3, look for at least 3 wet diapers and 3 stools in 24 hours. Wet diaper counts climb quickly from here, reaching 6 or more per day by the end of the first week. Stools will transition from the dark, tarry meconium of the first two days to a lighter, seedy yellow as your milk transitions.
Other reassuring signs include your baby seeming satisfied and relaxed after feedings, audible swallowing while nursing, and a gradual return to birth weight over the first two weeks. If your baby seems hungry constantly, never settles after feedings, or has fewer wet diapers than expected, those are signals to check in with your pediatrician about whether milk intake is on track.