A 6-day-old baby typically eats 1 to 2 ounces per feeding, about 8 to 12 times every 24 hours. That works out to roughly 12 to 24 ounces total per day, though the exact amount varies from baby to baby. Whether you’re breastfeeding, formula feeding, or doing a combination, the key at this age is frequent, small feedings that match your newborn’s tiny stomach.
Your Baby’s Stomach at 6 Days
At birth, a newborn’s stomach holds only about 1 to 2 teaspoons. By day 6, it’s growing quickly but still surprisingly small, roughly the size of a ping-pong ball by day 10, which holds about 2 ounces. This is why newborns need to eat so often. They physically can’t take in large volumes at once, so they make up for it with frequency. Trying to push more milk into a feeding won’t speed things up; it just overwhelms a stomach that isn’t ready for it.
Formula Feeding Amounts
If your baby is formula fed, offer 1 to 2 ounces per feeding every 2 to 3 hours. Some babies will drain 2 ounces consistently by day 6, while others hover closer to 1 to 1.5 ounces and eat more frequently. Both patterns are normal. The total daily intake at this stage generally falls between 12 and 20 ounces, depending on your baby’s size and appetite.
Don’t force your baby to finish a bottle. If they turn their head away or close their mouth after an ounce, that feeding is done. You can always offer more at the next one. Overfeeding formula can cause spit-up and discomfort, so follow your baby’s lead rather than aiming for a specific number on the bottle.
Breastfeeding Frequency and Duration
Breastfed babies should nurse at least 8 to 12 times in 24 hours, which means a feeding roughly every 2 to 3 hours around the clock. The American Academy of Pediatrics recommends unrestricted nursing on demand, meaning you feed whenever your baby shows hunger cues rather than watching the clock.
You can’t measure how many ounces a breastfed baby takes per session, and you don’t need to. A single nursing session typically lasts 10 to 20 minutes per breast at this age, though some babies are efficient feeders who finish faster and others like to linger. What matters is that your baby is latching well, swallowing audibly during the feeding, and producing enough wet and dirty diapers (more on that below). Cluster feeding, where your baby wants to nurse every 30 to 60 minutes for several hours straight, is common around this age and helps build your milk supply.
How to Tell Your Baby Is Hungry
Crying is actually a late hunger signal. By the time a 6-day-old is wailing, they’ve already been trying to tell you they’re ready to eat. The earlier cues to watch for include putting hands to their mouth, turning their head toward your breast or the bottle (called rooting), smacking or licking their lips, and clenching their fists. Catching these signals early makes feedings calmer for both of you, since a frantic baby has a harder time latching.
When your baby is full, the signs are equally clear. They’ll close their mouth, turn away from the breast or bottle, and their hands will relax and open. A satisfied newborn often looks drowsy or falls asleep at the end of a feeding.
Signs Your Baby Is Getting Enough
Since you can’t always measure what goes in, tracking what comes out is the most reliable way to know your baby is eating well. By day 5 or 6, a well-fed newborn produces at least 6 wet diapers per day. The number of dirty diapers varies, but breastfed babies at this age often have 3 or more loose, yellowish stools daily.
Weight is the other important marker. Most newborns lose up to 10% of their birth weight in the first few days, mostly from fluid loss. By day 6, that weight loss should be slowing down or starting to reverse. Your pediatrician will check weight at your baby’s first appointments to confirm they’re on track. Most babies regain their birth weight by 10 to 14 days old.
Warning Signs of Undereating or Dehydration
A 6-day-old who isn’t getting enough milk can become dehydrated quickly. Signs to watch for include fewer than 6 wet diapers in a day, a sunken soft spot on the top of the head, sunken eyes, few or no tears when crying, and unusual drowsiness or irritability. If your baby is increasingly difficult to wake for feedings or seems limp and uninterested in eating, that warrants immediate medical attention.
Also pay attention if your baby is still losing weight after day 5, or if feedings consistently last under 5 minutes at the breast with no audible swallowing. These can signal latch problems or low milk supply, both of which are fixable with the right support from a lactation consultant or pediatrician.