An 8-month-old typically drinks 24 to 32 ounces of formula per day, split across four to six bottles of about 6 to 7 ounces each. That total drops gradually as your baby eats more solid food, so the exact number depends on how much they’re eating at meals.
Daily Formula Amount at 8 Months
UC Davis Health recommends 6 to 7 ounces per feeding, every 3 to 4 hours during the day, for babies in the 8- to 9-month range. That works out to roughly 24 to 32 ounces across the day. The American Academy of Pediatrics offers a weight-based rule of thumb: about 2.5 ounces of formula per pound of body weight per day. An average 8-month-old weighing around 18 pounds would need roughly 45 ounces of total nutrition, but a good portion of that now comes from solid foods rather than formula alone.
The AAP also notes that babies should generally drink no more than about 32 ounces of formula in 24 hours. Consistently exceeding that amount can crowd out solid foods your baby needs for iron, zinc, and other nutrients that formula alone doesn’t supply in sufficient quantities at this age.
How Solids Change the Equation
At 8 months, your baby is likely eating two to three small meals of solid food each day. As those meals get bigger and more varied, formula intake naturally decreases. The CDC puts it simply: as your baby gradually eats more solid foods, they will gradually need less formula. Most 6- to 12-month-olds need formula or solid foods about five to six times in 24 hours, which typically looks like three meals and two to three bottle feedings.
There’s no precise ratio you need to hit. Some days your baby will be more interested in solids and drink less formula; other days they’ll want more bottles and push food away. Both patterns are normal as long as the overall trend is moving toward more solids over the coming months. Formula remains the primary source of calories and nutrition at 8 months, but solid foods are becoming an increasingly important part of the picture.
Per-Bottle Amounts and Feeding Schedule
Most 8-month-olds do well with bottles spaced about 3 to 4 hours apart. A common schedule looks something like this:
- Morning bottle: 6 to 7 ounces after waking
- Mid-morning: solid food meal (fruit, cereal, or a vegetable puree)
- Midday bottle: 6 to 7 ounces, often paired with or followed by a small lunch
- Afternoon bottle: 6 to 7 ounces
- Dinner: solid food meal
- Bedtime bottle: 6 to 7 ounces
Some babies drop to four bottles a day at this age, while others still want five. Either is fine. The total daily volume matters more than the number of individual bottles.
Knowing When Your Baby Has Had Enough
Ounce guidelines are useful starting points, but your baby is the best judge of how much they need. The CDC identifies several clear fullness cues to watch for: pushing the bottle away, closing their mouth, turning their head, or using hand motions and sounds to signal they’re done. Your baby does not need to finish every bottle. Forcing the last ounce can teach them to ignore their own hunger and fullness signals, which isn’t helpful long term.
On the flip side, if your baby consistently drains every bottle and still seems hungry, it’s reasonable to offer a bit more. Babies go through growth spurts around this age, and a temporary jump in intake is perfectly normal.
Weight-Based Calculations
If you want a more personalized number, the weight-based formula is straightforward. Multiply your baby’s weight in pounds by 2.5, and that gives you the approximate total ounces of nutrition (formula plus solids) they need per day. For babies between 6 and 12 months, a guideline from Australian health authorities suggests 90 to 120 milliliters of formula per kilogram of body weight per day, which translates to roughly 1.3 to 1.8 ounces per pound. That range is lower than the 2.5-ounce rule because it accounts for the calories your baby is getting from food.
In practice, this means an 18-pound baby might need anywhere from 24 to 32 ounces of formula depending on how much solid food they eat. A smaller baby at 16 pounds might be closer to 20 to 28 ounces, while a larger baby at 22 pounds could be on the higher end.
Water and Other Drinks
At 8 months, your baby can have small amounts of water, but it shouldn’t replace formula. The CDC recommends 4 to 8 ounces of water per day for babies between 6 and 12 months. Offering water in a sippy cup at mealtimes helps your baby practice drinking and supports digestion of solid foods. Juice, cow’s milk, and plant-based milks are not recommended at this age.
If your baby is getting at least 32 ounces of formula daily, they don’t need a separate vitamin D supplement, since formula is already fortified. Babies drinking less than 32 ounces may need supplemental vitamin D.