About the Baby's Milk Intake Calculator
This calculator estimates how much milk a baby needs from body weight. The most widely used guideline for the early months is about 150 millilitres of milk per kilogram of body weight per day. Multiply the baby's weight in kilograms by that rate to get a daily target, then divide by the number of feedings to get the amount for each feed.
The formula
- Daily total (mL) = weight (kg) × rate (mL/kg/day). The default rate is 150 mL/kg/day; a common range is 120-200.
- Per feeding (mL) = daily total ÷ feedings per day. More frequent feeds mean smaller amounts each time.
- Fluid ounces = millilitres ÷ 29.57. One US fluid ounce is about 29.57 mL.
Weight entered in pounds is converted to kilograms first (1 lb = 0.4536 kg). The US pediatric rule of thumb of about 2.5 fluid ounces per pound per day gives a similar result, roughly 165 mL/kg/day.
Putting the result in context
These figures are population guidelines, not targets every baby must hit. Newborns take small, frequent feeds; intake rises over the first weeks, and then the rate per kilogram gradually falls as the baby grows. Formula intake is usually capped near 960 mL (32 fl oz) per day. Babies feeding directly at the breast self-regulate and are normally fed on demand rather than to a measured volume.
When to consult a professional
Use this estimate as a starting point and follow your baby's hunger and fullness cues. If your baby is consistently taking much more or much less than expected, is not gaining weight, or you have any feeding concerns, consult your pediatrician or a licensed healthcare provider.