How much formula should a baby drink by weight?

The AAP's rule of thumb is about 2.5 ounces per pound of body weight per day, or about 165 ml per kg. A 10 lb baby would take around 25 oz in 24 hours. Most babies shouldn't need more than about 32 oz a day.

How many ounces should a newborn eat?

In the first days, about 1 to 2 ounces (30 to 60 ml) per feed every 2 to 3 hours, according to the CDC. By the end of the first month, most babies take 3 to 4 ounces about every 3 to 4 hours.

Is this calculator accurate for breastfed babies?

It gives a rough guide for bottles of expressed milk. Breastfed babies usually take smaller, more frequent feeds, and how much they take at the breast can't be measured directly. Diapers and weight gain are better signs they're getting enough.

What if my baby wants more than the calculator says?

Babies' needs change from day to day, especially during growth spurts. Follow hunger cues. If your baby consistently wants much more or much less than this range, discuss it with your pediatrician.

Does this tool store my baby's data?

No. The calculator runs in your browser and nothing is saved or sent. To keep a record of real feeds, use the Tot app.

Baby Feeding Calculator: Bottle Amount by Weight / Tot

Medically reviewed by Safi Ullah Khan · Written by Muneeb Rana · Last updated 21 October 2026

Quick answer: A baby feeding calculator estimates how much formula or expressed milk a baby usually takes. The AAP rule of thumb is about 2.5 oz (75 ml) per pound of body weight a day, up to about 32 oz (960 ml). Divide by the number of feeds and follow your baby's hunger and fullness cues.

TL;DR

Enter weight and age; the result is a typical range, not a target.
Daily total = 2.5 oz per lb (about 165 ml per kg), capped near 32 oz (AAP).
Newborns in the first week usually take only 1 to 2 oz per feed.

This baby feeding calculator turns your baby's weight and age into a typical bottle size and daily total, in ounces and millilitres. It uses the weight rule and age ranges published by the American Academy of Pediatrics (AAP) and the CDC. Babies regulate their own intake from day to day, so treat the number as a starting point and let your baby show you when they've had enough.

How to use the baby feeding calculator

Enter your baby's weight in lb/oz or kg.
Enter age in weeks or months (or birth date), and choose formula or expressed breast milk.
Optionally change the number of feeds per day. The tool suggests a typical number for the age.
Read the daily total and the per-feed range in oz and ml.
Log real bottles in Tot for a few days and compare with the estimate.

How the baby feeding calculator works

daily_oz   = min(weight_lb * 2.5, 32)        # AAP: about 2.5 oz per lb per day, rarely over 32 oz
daily_ml   = daily_oz * 29.57
per_feed   = daily_oz / feeds_per_day
clamp per_feed to the age range: week 1: 1-2 oz | weeks 2-4: 2-4 oz | 1-2 mo: 3-5 oz | 2-4 mo: 4-6 oz | 4-6 mo: 4-8 oz | 6-12 mo: 6-8 oz

Age	Typical per feed	Feeds in 24 hours	Source
First days	1-2 oz (30-60 ml)	8-12	CDC, AAP
End of month 1	3-4 oz (90-120 ml)	about every 3-4 h	AAP
6 months	6-8 oz (180-240 ml)	4-5, plus solids	AAP
6-12 months	depends on solids	formula or solids 5-6 times	CDC

For breastfed babies taking expressed milk, the AAP notes they usually take smaller, more frequent feeds than formula-fed babies, so the tool shows the lower part of the range.

Worked example

Maya is 6 weeks old and weighs 10 lb (4.5 kg). 10 × 2.5 = 25 oz a day (about 740 ml). At 7 feeds a day that's about 3.5 oz (105 ml) per bottle, inside the 3-5 oz range for her age. Her parents offer 3.5 oz, watch for fullness cues, and log each bottle in Tot.

Watch the baby, not just the bottle

Hunger cues include rooting, lip-licking and hands to the mouth; crying is a late sign. Fullness looks like turning away, slowing down, relaxed hands and falling asleep. The AAP says bottle-fed babies can overfeed because milk flows faster, and that it's better to offer less, since you can always give more. Read our guide to baby hunger cues.

When to talk to your pediatrician

Call if your baby regularly wants much more than 32 oz a day, refuses feeds, has fewer wet diapers than expected (see the diaper count calculator), vomits forcefully, or isn't gaining weight. Premature babies and babies with medical conditions often need a feeding plan from their care team instead of a general rule.

Track real feeds over a few days

One bottle tells you little; a few days of logs show the pattern. Tot's baby feeding tracker records each bottle in oz or ml and shows daily totals, so you can see whether your baby's intake matches the range and share the history with your partner and your pediatrician.

Download Tot free on the App Store or Google Play. Free with ads; optional Premium.

Sources

AAP HealthyChildren.org: Amount and Schedule of Baby Formula Feedings: www.healthychildren.org (accessed 21 October 2026)
AAP HealthyChildren.org: How Often and How Much Should Your Baby Eat?: www.healthychildren.org (accessed 21 October 2026)
CDC: How Much and How Often to Feed Infant Formula: www.cdc.gov (accessed 21 October 2026)
CDC: How Much and How Often to Breastfeed: www.cdc.gov (accessed 21 October 2026)
NHS: Formula milk, common questions: www.nhs.uk (accessed 21 October 2026)

Medical disclaimer:

Tot and this website give general information only. Feeding, sleep and growth ranges vary; always follow your pediatrician's advice. If your baby is unwell, contact your doctor or emergency services.

Baby Feeding Calculator: Bottle Amount by Weight