Baby formula calculator
Enter your baby's weight and the number of feeds a day to estimate how much formula to offer in total and per bottle. It uses the American Academy of Pediatrics rule of thumb. Babies vary: follow their hunger cues and your pediatrician's advice.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Choose kilograms and milliliters or pounds and fluid ounces.
- Enter the baby’s current weight.
- Enter how many feeds a day your baby usually has.
- Read the daily amount and the amount per feed.
How it works
- Daily formula = weight in pounds × 2.5 fl oz. In metric terms that is about 163 mL per kg.
- If the result is above 32 fl oz, the daily amount is limited to 32 fl oz (946 mL).
- Per feed = daily amount ÷ feeds a day.
Worked example
A baby weighs 4 kg (8.82 lb) and feeds 8 times a day. 8.82 × 2.5 = 22.0 fl oz, which is 652 mL a day, or 652 ÷ 8 = 81 mL per feed.
A 9 lb baby with 8 feeds: 9 × 2.5 = 22.5 fl oz a day, 2.8 fl oz per feed.
Tips
- Weigh the baby regularly; the amount grows with the weight.
- Prepare formula exactly as the package says; extra powder or water changes the calories.
- Premature babies and babies with health conditions often have different needs.
- This page is for information and does not replace advice from your pediatrician or health visitor.
Frequently asked questions
How much formula does a baby need?
The American Academy of Pediatrics gives a rule of thumb of about 2½ ounces (75 mL) a day for every pound of body weight, which is about 163 mL per kilogram. Most babies should not need more than about 32 ounces (950 mL) in 24 hours.
How many feeds a day are usual?
Newborns usually feed 8 to 12 times a day, every 2 to 3 hours. As babies grow they usually take more at each feed and need fewer feeds.
My baby drinks less or more than the result. Is that a problem?
Not necessarily. The figure is an average. Babies regulate their intake from feed to feed; steady weight gain, wet diapers and contentment matter more. Talk to your pediatrician if you are unsure.
Does it apply after solids are started?
Less so. Once solid foods are part of the diet, usually around 6 months, formula intake tends to fall, and the weight rule overestimates it.