Baby feeding calculator
Estimate how much formula or expressed milk a bottle-fed baby needs in a day, how much that is per feed, and how many feeds to expect at this age.
Estimated intake
Per day
25 oz
Per feed
3.1 to 4.2 oz
Feeds a day
6 to 8
How the estimate works
The standard rule of thumb for babies under 6 months is about 2.5 oz of formula per pound of body weight per day, roughly 150 ml per kg, capped near 32 oz a day. From 6 months the estimate steps down as solids take over part of the intake, reaching about 20 to 24 oz of milk a day by the first birthday.
Treat the number as a daily average, not a per-feed rule. Babies cluster feed, take a small bottle then a big one, and change appetite when growing or unwell. Six or more wet diapers a day and steady weight gain are the real confirmation.
Related reading
For amounts and frequency stage by stage, see the newborn feeding schedule by age and the diaper count chart. General guidance from AAP HealthyChildren and the NHS. This tool is general information, not medical advice.
Frequently asked questions
How many ounces of formula should my baby drink a day?
A common guide is about 2.5 oz per pound of body weight per day (roughly 150 ml per kg), up to a typical ceiling of about 32 oz a day for babies under 6 months.
How many ounces per feed?
Divide the daily total by the number of feeds. In practice that is about 2 to 3 oz per feed at 2 weeks, 4 oz at 1 month, 5 to 6 oz at 4 months and 6 to 8 oz at 6 months.
Does this work for breastfed babies?
Directly breastfed babies cannot be measured in ounces, so use it only for expressed milk or bottle feeding. For breastfeeding, diaper counts and weight gain are the signals that matter.
What if my baby drinks more or less than this?
Appetite varies day to day and babies cluster feed. Steady weight gain and six or more wet diapers a day matter far more than hitting an exact number.