An 11-week-old typically drinks 4 to 6 ounces per feeding, with most babies taking in roughly 24 to 32 ounces total over 24 hours. The exact amount depends on whether your baby is breastfed or formula-fed, how much they weigh, and whether they’re in the middle of a growth spurt. Here’s how to figure out what’s right for your baby specifically.
Per-Feeding and Daily Totals
At 11 weeks, your baby falls right between the second and third month milestones, so feeding volumes are in transition. During the second month, most babies take 2 to 4 ounces every 2 to 4 hours across 7 to 8 daily feedings. By month three, that shifts to 4 to 5 ounces every 4 to 5 hours across 6 to 8 feedings. Your 11-week-old is likely somewhere in the middle: 4 to 5 ounces per feeding, roughly 6 to 8 times a day.
A useful rule of thumb from the American Academy of Pediatrics: babies need about 2.5 ounces of formula per day for every pound of body weight. So if your 11-week-old weighs 11 pounds, that’s roughly 27.5 ounces spread across the day. A 13-pound baby would need closer to 32 ounces. This calculation gives you a personalized target rather than relying solely on age-based ranges.
Formula-Fed vs. Breastfed Babies
Formula-fed babies at this age typically drink 5 to 6 ounces per feeding, five to six times per day, according to Johns Hopkins Medicine. By three to five months, that increases to 6 to 7 ounces per feeding. Formula digests more slowly than breast milk, so formula-fed babies tend to go longer between feedings and take slightly larger volumes each time.
Breastfed babies feed more frequently, averaging 8 to 12 sessions in 24 hours, though each session delivers a smaller volume. Measuring exact ounces is harder when nursing directly, which is why pediatricians rely on weight gain and diaper output instead. If you’re pumping and bottle-feeding breast milk, the same principle applies: follow your baby’s hunger and fullness cues rather than forcing a set amount. Pushing a baby to finish a bottle, even one filled with breast milk, can lead to overfeeding and excess weight gain.
Your Baby’s Stomach Size
Between one and three months, a baby’s stomach holds about 4 to 6 ounces at a time. That physical limit is worth keeping in mind. If your baby consistently spits up large amounts after a feeding, they may be taking in more than their stomach can comfortably hold. Offering slightly less per bottle and feeding a bit more frequently often solves the problem.
The 3-Month Growth Spurt
Growth spurts happen at predictable intervals: around 2 to 3 weeks, 6 weeks, 3 months, and 6 months. Your 11-week-old may be entering or right in the middle of the 3-month spurt. During a growth spurt, babies get fussier and want to eat more often, sometimes as frequently as every 30 minutes. This can feel alarming, but it’s temporary, usually lasting a few days.
For breastfed babies, the increased nursing signals the body to produce more milk. For formula-fed babies, you can offer an extra ounce or two per bottle or add a feeding to the day. Once the spurt passes, your baby will settle back into a more predictable pattern, often with slightly larger feedings than before.
How to Tell Your Baby Is Getting Enough
Ounce counts are guidelines, not rules. The most reliable signs that your baby is eating enough are steady weight gain and adequate diaper output. After the first week of life, babies should produce at least 6 wet diapers per day. Most 11-week-olds gain about 5 to 7 ounces per week, though your pediatrician tracks this on a growth curve that accounts for your baby’s individual pattern.
Hunger cues to watch for include rooting (turning their head toward anything that touches their cheek), sucking on hands, and fussiness. Crying is actually a late hunger signal. On the fullness side, a baby who turns away from the bottle or breast, closes their mouth, or relaxes their hands is telling you they’re done. Trusting these cues matters more than hitting an exact ounce number.
When Intake Seems Too Low or Too High
If your 11-week-old consistently takes less than 20 ounces in a full day, seems lethargic, produces fewer than 6 wet diapers daily, or isn’t gaining weight at checkups, that’s worth discussing with your pediatrician. On the other end, most babies shouldn’t need more than 32 ounces of formula per day at this age. Consistently exceeding that, combined with frequent large spit-ups, could mean feedings need to be spread out differently or that something else, like reflux, is at play.
Every baby is different. Some are efficient eaters who take larger volumes less often, while others prefer smaller, more frequent meals. Both patterns are normal as long as your baby is growing steadily and producing enough wet diapers.