Most newborns need about 1 to 2 ounces of milk per feeding by the end of their first week, working up to 3 to 5 ounces per feeding by one month old. But the first few days look very different from even a week later, because a newborn’s stomach is remarkably small and grows rapidly. Here’s what to expect at each stage.
Your Baby’s Stomach in the First Month
On the day they’re born, a newborn’s stomach holds just 5 to 7 milliliters at a time. That’s roughly one teaspoon. Within those first 24 hours, each feeding delivers only about 2 to 10 milliliters of milk, which is less than a standard dose of cough syrup. It sounds impossibly small, but it’s exactly what your baby’s body is designed for.
By day three, stomach capacity roughly triples to about 22 to 27 milliliters, and your baby takes in around 1 ounce per feeding. At one week, the stomach holds 1.5 to 2 ounces. By one month, your baby can take in 3 to 5 ounces at each feeding. This rapid expansion is why feeding amounts change so quickly in those early weeks.
How Often Newborns Need to Eat
Breastfed newborns typically eat 8 to 12 times in 24 hours, which works out to roughly every 2 to 3 hours around the clock. Formula-fed babies generally eat slightly less often, around 6 to 8 times per day, because formula digests more slowly than breast milk.
A useful rule for formula feeding: your baby needs about 2.5 ounces of formula per day for every pound of body weight. So an 8-pound baby would need roughly 20 ounces spread across the day’s feedings. This is an average, not a rigid target. Some days your baby will eat a bit more, others a bit less.
Cluster Feeding Is Normal
Cluster feeding, when your baby wants to eat every hour or even more frequently for a stretch, starts the day they’re born. It happens partly because that tiny stomach can only hold so little at once, so your baby needs to refuel often. In older newborns, cluster feeding tends to show up in the evenings and can last several hours.
Cluster feeding doesn’t mean your milk supply is low or that your baby isn’t getting enough. It’s a normal pattern that actually helps stimulate milk production. The total amount your baby takes in over 24 hours stays roughly the same. It’s just bunched into shorter intervals during those stretches, with longer gaps in between.
How to Tell if Your Baby Is Hungry
Watching for hunger cues is more reliable than following a strict schedule. Early hunger signs include putting hands to mouth, turning their head toward your breast or the bottle (called rooting), smacking or licking their lips, and clenching their fists. Crying is actually a late sign of hunger. A baby who’s already crying may be harder to latch or settle, so try to catch those earlier signals.
When your baby is full, the cues are equally clear. They’ll close their mouth, turn their head away from the breast or bottle, and their hands will relax and open. Following these signals rather than pushing your baby to finish a set amount helps prevent overfeeding, especially with bottle-fed babies who can’t control the flow as easily.
Signs Your Baby Is Getting Enough
Diapers are your best daily gauge. In the early days, a simple rule applies: your baby should produce roughly one wet diaper and one dirty diaper for each day of life. One of each on day one, two of each on day two, three of each on day three, and so on through the first week. After that first week, expect six or more wet diapers a day.
Weight is the other key marker, though the pattern can be alarming if you’re not prepared for it. Nearly all newborns lose weight in the first few days. Among babies delivered vaginally, close to 5% lose 10% or more of their birth weight by 48 hours. For babies delivered by cesarean, the numbers are higher: more than 25% lose at least 10% of their birth weight by 72 hours. This is normal and expected. Most babies regain their birth weight by 10 to 14 days old. Your pediatrician will track this at early checkups.
Signs of Overfeeding
Overfeeding is more common with bottle feeding than breastfeeding, because a baby at the breast can regulate their own intake more easily. An overfed baby may spit up more than usual and have frequent loose stools. If your baby seems uncomfortable, gassy, or fussy after feedings even though they didn’t show hunger cues beforehand, you may be offering too much at once.
The fix is straightforward: offer smaller amounts more frequently, pace the bottle feeding by holding it more horizontally and pausing every few minutes, and always follow your baby’s fullness cues. If they turn away or close their mouth, the feeding is done, even if there’s milk left in the bottle.
Vitamin D for Breastfed Babies
Breast milk provides nearly everything a newborn needs, with one notable exception. The American Academy of Pediatrics recommends that breastfed and partially breastfed infants receive 400 IU of vitamin D daily, starting in the first few days of life. Vitamin D drops designed for infants are available over the counter and are given as a single drop per day. Formula-fed babies who drink at least 32 ounces of formula daily get enough vitamin D from the formula itself and typically don’t need a supplement.