Newborn Poop Colour Guide: What's Normal and When to Worry

Newborn poop changes a lot in the first week. It starts as sticky, black-green meconium, turns greenish-brown around days 3 to 4, and by the end of the first week is usually mustard-yellow and seedy in breastfed babies, or pale yellow to tan and a little firmer in formula-fed babies. Green, yellow and brown are all normal. The colours to act on are red, black after the first few days, and pale, white or clay-coloured stools.

This guide walks through what is normal day by day, includes a colour chart, and explains constipation, diarrhoea and when to see a doctor in Singapore.

The first week: from meconium to milk poop

Your baby’s first poos are meconium: thick, sticky, tar-like and dark green to black. It is made of material your baby swallowed in the womb and is usually passed within the first 24 to 48 hours. It can be hard to wipe off, so a little water or a smear of barrier cream on clean skin makes the next clean-up easier. If you have booked a newborn photoshoot for the first week or two, pack extra nappies and wipes for the session.

As your baby takes in more milk, stools become “transitional”: looser and greenish-brown, usually around days 3 to 4. SingHealth’s newborn care advice describes the move from blackish stools in the first two to three days to golden yellow or yellowish-brown over the first week.

This change is also a useful feeding check. If your baby is still passing black meconium on day 4 or 5, or has few wet nappies, let your doctor or lactation nurse know, as it can mean your baby is not getting enough milk. It ties in with the day 3 to 5 check covered in our newborn jaundice guide.

Breastfed vs formula-fed poop

Breastfed babies

Breastfed poop is typically mustard-yellow, runny or soft, and often has small seedy or curdy bits. It has a mild, slightly sweet smell. In the early weeks many breastfed babies poo after most feeds, but from around six weeks some go several days without a poo. If the stool is soft when it comes and your baby is feeding well and comfortable, this can be normal.

Formula-fed babies

Formula poop tends to be pale yellow, tan or light brown, thicker, like peanut butter, and smellier. Formula-fed babies usually poo at least once a day or every other day. Some formulas, especially those with added iron, can make stools greener or darker, which is not a concern. If you combination feed, expect something in between.

Newborn poop colour chart

Use this as a general guide. Colours can look different under indoor lighting, so check in daylight if you are unsure, and take a photo of the nappy to show your doctor.

Colour	What it usually means	What to do
Black-green, tar-like (days 1 to 3)	Meconium	Normal in the first days
Mustard or golden yellow	Typical breastfed poop	Normal
Pale yellow, tan or light brown	Typical formula-fed poop	Normal
Green	Fast digestion, iron in formula, a tummy bug, or later green foods	Usually normal if your baby is well
Brown	Common with formula and after solids start	Normal
Red streaks or red poop	Blood, which can come from a small tear from straining, swallowed blood from cracked nipples, cow’s milk protein allergy or infection	See a doctor, and keep the nappy
Black after the first week	Can be digested blood, or iron supplements	See a doctor unless your doctor has prescribed iron
Pale, white, grey or clay-coloured	Possible lack of bile, which can signal a liver problem such as biliary atresia	See a doctor promptly, the same day or next working day

Why pale or white poop matters

Bile from the liver is what gives poop its yellow, green or brown colour. If stools are persistently pale, chalky white or grey, bile may not be reaching the gut. One rare but serious cause is biliary atresia, where the bile ducts are blocked. It usually shows up between two and eight weeks of age as pale stools, dark yellow urine and jaundice that lasts beyond two weeks.

Biliary atresia is treated with surgery, and outcomes are much better when it is done early, ideally within the first two months of life. This is why doctors take pale stools seriously even in a baby who looks well and is feeding normally.

Constipation: what counts and what helps

Straining, going red in the face and grunting are very common in young babies and do not mean constipation. Babies are learning to relax their bottom muscles while pushing with their tummy, which takes practice. What matters is the poop itself.

Your baby may be constipated if their stools are hard, dry or pellet-like, they seem in pain passing them, or there are streaks of blood from a small tear. Constipation is uncommon in exclusively breastfed babies and more common in formula-fed babies and after solids start.

Check formula preparation. Make formula exactly as the label says. Too much powder can make stools harder.
Gentle tummy massage in clockwise circles, and “bicycle legs” while your baby lies on their back, may help.
A warm bath can help your baby relax.
Do not give water, juice or home remedies to babies under six months unless your doctor advises it, and do not use laxatives or suppositories without medical advice.

If constipation lasts more than a few days, keeps coming back, or your baby has a swollen tummy or is vomiting, see your doctor.

Diarrhoea and dehydration

Because breastfed poop is naturally loose, diarrhoea is judged by change: a sudden increase in how often your baby poos, much more watery stools, or stools with mucus or blood. Diarrhoea can be caused by an infection and is more worrying in young babies because they can become dehydrated quickly.

Keep feeding. Breastfeed more often or continue formula as usual, and follow your doctor’s advice on oral rehydration solution. Watch closely for dehydration:

Fewer wet nappies than usual, or dark, strong-smelling urine
A dry mouth, or crying without tears
A sunken soft spot on the top of the head
Unusual sleepiness, floppiness or irritability

When to see a doctor

See your paediatrician or polyclinic the same day if your baby has blood in their stool, black stools after the first week, pale or white stools, diarrhoea with signs of dehydration, or constipation with a swollen tummy or vomiting. Also see a doctor if your newborn has not passed meconium within 48 hours of birth.

Go to the Children’s Emergency at KKH or NUH, or call 995, if your baby is very drowsy, floppy or hard to wake, has green (bile-coloured) vomit, a very swollen and tender tummy, or is under three months with a temperature of 38°C or higher. Our guide to baby fever and when to see a doctor covers temperature red flags in more detail.

The bottom line

Poop goes from black meconium to yellow within about a week, and after that green, yellow and brown are all within the normal range. Frequency varies widely, especially in breastfed babies. Keep an eye out for red, black or pale stools, hard pellets with pain, or watery diarrhoea with fewer wet nappies, and get pale stools checked promptly. For more on the first weeks, see our umbilical cord care guide, our guide to the newborn hearing test and the newborn care section.

How many times a day should a newborn poop?

It varies. In the first weeks, many breastfed babies poo after most feeds, while formula-fed babies often go once or twice a day. From around six weeks, some breastfed babies go several days between poos. What matters is that stools are soft and your baby is feeding well and gaining weight.

Is green poop normal for a baby?

Usually, yes. Green poop can come from fast digestion, iron in formula, a minor tummy bug or, later, green foods. If your baby is well, feeding normally and the green poop is not accompanied by diarrhoea, it is not a concern.

Why is my baby's poop white or pale?

Pale, white, grey or clay-coloured poop can mean bile is not reaching the gut, which may indicate a liver problem such as biliary atresia. It needs to be checked by a doctor promptly, even if your baby seems well. Take a photo of the nappy to show them.

Can I give my constipated newborn water?

Babies under six months generally do not need water, and giving it can fill them up without nutrition. Speak to your doctor first. Check that formula is prepared exactly as the label says, and try tummy massage and bicycle legs.