Milk supply checker
Enter your baby's age, nappy counts, feeds and weights and this tool checks each against the published NHS or AAP figure for that age, then tells you which signs are reassuring and which need a call today. It returns no millilitre figure, because nothing at home can measure how much milk you make.
Milk supply checker
No sign-up · PrivateCount the day of birth as day 0. Almost every figure below changes across the first week, so this is the field that decides what "enough" looks like.
The two differ on stool counts — the NHS asks for at least 2 soft yellow poos a day from day 4, the AAP for 3 to 4 from day 5. Pick the one your health service follows.
NHS tip: disposables are hard to judge. Take an unused nappy and add 2 to 4 tablespoons of water — that is what a properly wet one feels like.
Count anything more than a smear. Breastfed poo is runny and does not smell.
The colour changes on a schedule of its own: black and tarry for the first days, then greenish-brown, then yellow. Still black after day 4 is worth a call.
Count every feed, including short ones and the cluster of them in the evening. A feed that lasted five minutes still counts.
Optional, but it turns the weight question from a guess into arithmetic.
Only if you are working in pounds and ounces. 7 lb 11 oz means 7 above and 11 here.
The most recent weight from a midwife, health visitor or clinic. Bathroom scales are not accurate enough for this.
The NHS lists "you do not feel any pain in your breasts or nipples when your baby is feeding" among the signs of good attachment. Pain is a symptom, not a stage.
Fill in the fields above to see your result.
Nothing you type leaves your device. The whole calculation runs in your browser.
How this is calculated
FormulaHow the check works
There is no volume arithmetic here, because there is none to do. Each sign you enter is compared against the published figure for your baby's age in whole days, counting the day of birth as day 0. The one calculation is the weight line:
weight change = (weight now − birth weight) ÷ birth weight × 100
That reading is checked against the band the AAP publishes: a well-nourished newborn should “lose no more than 8%-10% of their birth weight in the first few days after birth, before starting to gain weight again.” Past 10% the tool stops being reassuring and asks you to contact someone today.
The published thresholds
- Wet nappies. NHS: “In the first 48 hours, your baby is likely to have only 2 or 3 wet nappies”, then “From day 5 onwards... at least 6 heavy, wet nappies every 24 hours.” AAP: 2 to 3 a day in the first few days, at least 5 to 6 after the first 4 to 5 days, and “6 or more wet diapers per day, with nearly colorless or pale yellow urine, by 5 to 7 days old.”
- Stools. NHS: “From the fourth day, they should do at least 2 soft, yellow poos the size of a £2 coin every day for the first few weeks.” AAP is stricter: 1 or 2 blackish tarry stools on days 1 and 2, at least two turning greenish to yellow on days 3 and 4, then “at least 3 to 4 of these per day” by days 5 to 7. The tool reports whichever body you pick and never averages them.
- Feeds. NHS: “your baby should feed at least 8 to 12 times, or more, every 24 hours during the first few weeks.” AAP: “Nurse at least 8 to 12 times every 24 hours.”
- Weight. NHS: “Your baby gains weight steadily after the first 3 to 4 days.” The NHS Best Start in Life pages put the same turning point at two weeks; both sentences are the NHS, they do not agree, and the tool says so rather than picking one.
- At the feed. NHS signs of a feed going well: hearing and seeing swallowing, cheeks staying rounded rather than hollow, your baby coming off the breast on their own, breasts feeling softer afterwards, and a nipple that is “not flattened, pinched or white” after the feed.
Why no millilitre figure is produced
Because no home method measures milk production. Breast fullness settles over the early weeks without production falling, and pumped output is not what a baby extracts — Unicef UK has published a piece dismantling the pump “yield test” directly. What is left is what goes in, what comes out, and the direction of the weight, which is the assessment a midwife makes.
The question nothing at home can answer
How much milk am I making? There is no instrument for it. You cannot see into a breast, and the two things people reach for instead are both poor substitutes.
The first is fullness. Breasts feel noticeably full in the early weeks and then settle down, usually somewhere between six and twelve weeks, without production falling at all. That softening catches out almost everyone, and it starts more unnecessary formula top-ups than any other single thing.
The second is the pump, and it is worse, because it produces a number. Unicef UK Baby Friendly has published a piece taking the idea apart: the belief that a woman can "measure her milk supply by doing a yield test and using a pump to extract milk which apparently will be the equivalent amount to what her baby extracts during a feed using an entirely different process." A baby and a pump do not do the same job. Plenty of people who feed perfectly well pump almost nothing, and the reading makes them doubt something that was never in doubt.
What the guidance actually measures instead
Both the NHS and the AAP answer "is my baby getting enough" the same way: by what goes in, what comes out, and which direction the weight is going. Those signs are published, they are specific, and they change day by day across the first week — which is why the age field on this tool decides everything else.
Wet nappies are the clearest. Only two or three in the first 48 hours, which surprises people who are counting from day one. Then they climb, and from day five the NHS wants at least six heavy ones every 24 hours. If you cannot tell whether a disposable is wet, the NHS suggests pouring two to four tablespoons of water into an unused one so you know what you are feeling for.
Stools follow a schedule of their own: black and tar-like meconium for the first days, greenish-brown as the milk comes through, then soft and yellow. The NHS asks for at least two yellow ones a day from day four, each about the size of a £2 coin. The AAP asks for three to four by days five to seven. Still black at day five is worth a phone call.
Weight is the real measurement, and it is the one you cannot take at home. Bathroom scales are not accurate enough for a baby. What this tool does with the figure from your midwife or clinic is check it against the AAP's published band — no more than 8 to 10% below birth weight in the first few days, then gaining again.
The sign people skip
Pain. The NHS lists "you do not feel any pain in your breasts or nipples when your baby is feeding" among the signs of good attachment, and a nipple that comes out flattened, pinched or white among the signs it is not. Painful feeding is a symptom, not a stage you get through. It is also the most fixable item on the whole list, because attachment is usually correctable in one session with someone who knows what they are looking at.
The same goes for hearing swallowing. Rapid sucks at the start, then long rhythmic sucks with audible swallows and occasional pauses, is what an effective feed sounds like. If you never hear it, that is information worth taking to someone.
Feeding often is not a sign of failure
The NHS is blunt: "It's not possible to overfeed a breastfed baby." A newborn feeding eight to twelve times in 24 hours is normal, feeding again forty minutes after the last one is normal, and the long evening cluster of feeds that arrives around three weeks is normal. None of them means you are running out. Unicef UK has published a piece on precisely this — the modern obsession with the interval between feeds, which it traces to mid-twentieth-century formula norms rather than to any evidence about breastfeeding.
What to do if a sign is off
Ask early. The NHS list of things that affect supply is mostly a list of fixable things: attachment and positioning, not feeding often enough, bottles or a dummy before feeding is established, separation, illness, tongue-tie, and anxiety or depression. "With skilled help, lots of these problems can be sorted out."
What raises supply is unglamorous and free: feed as often and as long as your baby wants, offer both breasts and alternate which you start with, hold your baby skin to skin, and get someone to watch a feed. Contact your midwife, health visitor or GP today if your baby is more than 10% below birth weight, is having fewer than four wet nappies in 24 hours after day five, is still passing black stools after day five, or is very sleepy and hard to rouse. The National Breastfeeding Helpline is open 24 hours a day on 0300 100 0212.
Sources
- Breastfeeding: is my baby getting enough milk? — NHS, accessed
- Breastfeeding: the first few days — NHS, accessed
- Milk supply — NHS (Best Start in Life), accessed
- How to Tell if Your Breastfed Baby is Getting Enough Milk — American Academy of Pediatrics (HealthyChildren.org), accessed
- How Often and How Much Should Your Baby Eat? — American Academy of Pediatrics (HealthyChildren.org), accessed
- Breastfeeding: the dangerous obsession with the infant feeding interval — Unicef UK Baby Friendly Initiative, accessed