A newborn starts with just 1 to 2 ounces per feeding in the first few days of life, gradually increasing to 2 to 3 ounces by the end of the first two weeks. That small amount matches their tiny stomach, which at birth is roughly the size of a marble and holds only 1 to 2 teaspoons of milk. Here’s how feeding volumes change week by week and how to tell your baby is getting enough.
How Much Per Feeding in the First Week
For formula-fed newborns, the CDC recommends starting with 1 to 2 ounces every 2 to 3 hours. That means 8 to 12 feedings in a 24-hour period. It sounds like a lot of sessions for very little milk, but a newborn’s stomach simply can’t hold more than that. By day 10, their stomach grows to roughly the size of a ping-pong ball, holding about 2 ounces at a time.
Breastfed babies take in even smaller amounts in the first few days, since a mother’s early milk (colostrum) comes in concentrated drops rather than full ounces. The volume rises naturally as milk production increases, typically around days 3 to 5. You won’t be able to measure exactly how much a breastfed baby drinks at each session, which is normal. Diaper output and weight gain are more reliable indicators than trying to track ounces.
Feeding Volumes From Weeks 1 Through 4
Intake increases steadily over the first month:
- First few days: 1 to 2 ounces per feeding
- 1 to 3 weeks old: 2 to 3 ounces per feeding
- 3 weeks and older: 3 to 5 ounces per feeding
These ranges apply to both breastfed and formula-fed babies, though breastfed infants tend to take slightly smaller, more frequent feeds. Formula-fed babies who reach about 32 ounces per day don’t need a separate vitamin D supplement, since formula is already fortified. Breastfed babies typically do need supplemental vitamin D regardless of intake volume.
Why Feedings Are So Frequent
New parents are often surprised by how often a newborn needs to eat. Every 2 to 3 hours is the baseline, but many babies eat even more frequently during what’s called cluster feeding. This is when your baby wants several short feeds bunched together, sometimes every hour, often in the evening. It doesn’t necessarily mean something is wrong. Cluster feeding helps stimulate milk production in breastfeeding mothers and compensates for the natural dip in milk supply that happens later in the day.
That said, persistent cluster feeding that goes on for multiple days straight can sometimes signal a latch problem or low milk supply. If your baby never seems satisfied after feedings and isn’t gaining weight, that’s worth bringing up with your pediatrician or a lactation consultant.
How to Tell Your Baby Is Getting Enough
Since you can’t peer inside your baby’s stomach, external signals matter. The most reliable day-to-day check is diaper output. After day 5, a well-fed newborn produces at least 6 wet diapers in 24 hours. Fewer than that can signal inadequate intake.
Weight gain is the other key marker. Healthy newborns gain about 1 ounce per day in the first few months. Most babies lose a small percentage of their birth weight in the first few days, then regain it by about 10 to 14 days old. Your pediatrician will track this at early checkups.
Reading Hunger and Fullness Cues
Rather than watching the clock, it helps to learn what your baby looks like when hungry versus full. Early hunger cues include putting hands to mouth, turning their head toward the breast or bottle (called rooting), smacking or licking lips, and clenching their fists. Crying is actually a late hunger signal, so ideally you’d catch the earlier signs and start a feeding before your baby gets upset.
A baby who’s had enough will close their mouth, turn their head away from the breast or bottle, and visibly relax their hands. Trying to push more milk after these signals can lead to spit-up and teaches your baby to override their own fullness cues. Let them decide when the feeding is done, even if the bottle isn’t empty.
Formula vs. Breastfeeding Differences
The total daily intake ends up roughly similar for both groups by the end of the first month, but the pattern looks different. Breastfed babies typically feed more often because breast milk digests faster than formula. Formula-fed babies may go slightly longer between sessions and take a bit more per feeding to compensate.
If you’re supplementing with formula while also breastfeeding, the per-session volumes will vary depending on how much breast milk your baby got first. There’s no universal formula for splitting the two. The best approach is to follow your baby’s hunger and fullness cues and use diaper counts and weight checks to confirm they’re on track.