For example, an 8 lb baby takes about 20 fl oz (591 ml) a day and a 12 lb baby about 30 fl oz (887 ml).
How the baby formula calculator works
BabyFormulaCalc uses the common paediatric rule of thumb that a formula-fed baby drinks about 2.5 fluid ounces per pound of body weight a day (about 150 ml per kg), up to a maximum of about 32 fl oz. Breastfed babies drinking from a bottle take a fairly steady 25 fl oz a day from about one to six months, so breast milk is not scaled up with weight after the first month. The daily amount is split over a typical number of feeds for the baby’s age, which you can change. For formula it also shows how many level scoops go in each bottle, at one scoop per 2 fl oz of water (most US powders) or per 30 ml (many UK and European powders), and how many cans you will use in a week and a month.
Baby formula chart by weight
| Baby’s weight | Formula per day | Millilitres per day |
|---|---|---|
| 6 lb (2.7 kg) | 15 fl oz | 444 ml |
| 7 lb (3.2 kg) | 17.5 fl oz | 518 ml |
| 8 lb (3.6 kg) | 20 fl oz | 591 ml |
| 9 lb (4.1 kg) | 22.5 fl oz | 665 ml |
| 10 lb (4.5 kg) | 25 fl oz | 739 ml |
| 11 lb (5 kg) | 27.5 fl oz | 813 ml |
| 12 lb (5.4 kg) | 30 fl oz | 887 ml |
| 13 lb (5.9 kg) | 32 fl oz | 946 ml |
| 14 lb (6.4 kg) | 32 fl oz | 946 ml |
| 16 lb (7.3 kg) | 32 fl oz | 946 ml |
| 18 lb (8.2 kg) | 32 fl oz | 946 ml |
Typical feeds per day by age
| Age | Feeds per day | Per feed at 25 fl oz a day |
|---|---|---|
| 0–1 month | 8 | 3.1 fl oz |
| 1–2 months | 7 | 3.6 fl oz |
| 2–4 months | 6 | 4.2 fl oz |
| 4–6 months | 5 | 5 fl oz |
| 6–12 months | 4 | 6.3 fl oz |
These are averages, not targets. Babies vary from day to day and go through growth spurts. Feed on cue, never force a baby to finish a bottle, and talk to your paediatrician or health visitor about weight gain, prematurity, reflux or special formulas. This is not medical advice.
Frequently asked questions
How much formula for a 2 month old?
Typically 4–5 fl oz per feed, 6–7 feeds a day, around 24–32 fl oz in total depending on weight.
How much formula for a 4 month old?
About 4–6 fl oz per feed, 5–6 feeds a day, up to about 32 fl oz.
Is more than 32 oz of formula too much?
Most babies do not need more than about 32 fl oz a day; ask your paediatrician if your baby regularly wants more.
Is BabyFormulaCalc free?
Yes, with no sign-up or ads, and your numbers stay in your browser.
Is this medical advice?
No. It is a general guide. Feed on cue and ask your paediatrician or health visitor about your baby’s feeding.