How many diapers, and what color?

From the CDC’s Newborn Breastfeeding Basics, for breastfed babies. The CDC credits the table to USDA WIC Breastfeeding Support.

“In the first few days after birth, a baby should have 2 to 3 wet diapers each day. After the first 4 to 5 days, a baby should have at least 5 to 6 wet diapers a day. Stool (poop) frequency varies more. However, by the fourth day your baby should be having at least 4 stools a day. The exact number depends whether they are breastfed or formula-fed.” American Academy of Pediatrics

“Have 6 or more wet diapers per day, with nearly colorless or pale yellow urine, by 5 to 7 days old.” American Academy of Pediatrics

“Within 3 to 5 days, both breast-fed and bottle-fed babies will wet about 8 diapers every 24 hours.” American Academy of Pediatrics

“From day 5 onwards, wet nappies should start to become more frequent, with at least 6 heavy, wet nappies every 24 hours. In the first 48 hours, your baby is likely to have only 2 or 3 wet nappies.” NHS

“Six or more wet diapers in a 24-hour period.
Stools that are yellow, soft and seedy. Early on, these may come after every feeding. After the first month, stools may not be as frequent (1 bowel movement every 2 to 7 days), but they should be soft and yellow.” Canadian Paediatric Society

“After the first week up to about 6 weeks, your baby might have 6 or more poops a day (24 hours). After about 6 weeks, your baby may have fewer poops each day.” CDC

“Have 1 or 2 bowel movements per day on days 1 and 2, with blackish, tarry stools; then, at least two stools that are beginning to appear greenish to yellow on days 3 and 4.” American Academy of Pediatrics

“By 5 to 7 days old, your baby's stools should be yellow and loose, with small curds. They should have at least 3 to 4 of these per day. When your breast milk production increases, your baby will often produce stool with each feeding for the first month of life.” American Academy of Pediatrics

“By three to six weeks of age, some breastfed babies have only one bowel movement a week and still are normal.” American Academy of Pediatrics

“Between 4 and 8 weeks of age, some breastfed babies change to normal infrequent stools.
They can pass 1 large soft stool every 4 to 7 days.” AAP KidsDoc (Barton Schmitt, MD)

“Babies do 2 or more poos a day in the first week of life. This goes down to an average of 2 a day by the time they're 1 year old. Newborn babies who are breastfed may poo at each feed in the early weeks, then, after about 6 weeks, not have a poo for several days. Formula-fed babies may poo up to 5 times a day when newborn, but after a few months this can go down to once a day.” NHS

“If your baby is formula-fed, they should have at least one bowel movement a day. If they have fewer than this and appear to be straining, they may be constipated. Check with your pediatrician for advice on how to handle this problem.” American Academy of Pediatrics

“Some babies poo several times a day, and some babies poo only a few times a week. This is normal.” Raising Children Network

“Baby poop can vary in color. In the first week, baby poop changes from black or dark green to a yellow color.” CDC

“After the first week, poop from babies who have received only breast milk will be yellow and can look seedy.” CDC

“For the first few days after birth, your baby's first bowel movements will be a substance known as meconium. This thick black or dark green substance filled their intestines before birth, and once passed, the stools turn yellow-green.” American Academy of Pediatrics

“Meconium Stools are dark greenish-black, thick and sticky. They are passed during the first 2 days of life.
Transitional Stools (a mix of meconium and milk stools) are greenish-brown and loose. They are passed day 3 to 4 of life.” AAP KidsDoc (Barton Schmitt, MD)

“If your baby is breastfed, their stools soon should be yellow liquid mixed with some particles that remind many parents of little seeds.” American Academy of Pediatrics

“If they're formula-fed, their stools usually will be tan or yellow in color. They will be firmer than a breastfed baby's, but should be no firmer than soft clay. Green stools are not unusual, either, and they should not cause alarm.” American Academy of Pediatrics

“In reality, once your baby has pooped enough to get rid of the tarry meconium, all the varying shades of yellow, brown, and even green that may follow are considered perfectly acceptable. Mustardy yellow is the color of choice for most breastfed babies. For those who are formula fed, it's yellow-tan with hints of green.” American Academy of Pediatrics

“Breastfed babies usually produce mustard-yellow, seedy-looking poop, while bottle-fed babies put out different shades of pasty brown. This transition from dark, sticky poop to lighter-colored output suggests your baby is getting plenty to eat.” American Academy of Pediatrics

“Your baby's first poo is called meconium. This is sticky and greenish-black. Some babies may do this kind of poo during or after birth, or some time in the first 48 hours. After a few days the poo will change to a yellow or mustard colour. Breastfed babies' poo is runny and doesn't smell. Formula-fed babies' poo is firmer, darker brown and more smelly.” NHS

“The best way to tell if your baby is getting enough milk is to keep track of wet and dirty diapers. As your milk changes, your baby's poops will too. At first, poops will be black and tarry. Then they'll be greenish to yellowish. Then they will become yellow, loose, and seedy. Around 10-15 days after delivery, your baby may poop after every feeding or less often.” USDA WIC Breastfeeding Support

“However, if there are large amounts of blood, mucus, or water in the stool, call your pediatrician immediately.” American Academy of Pediatrics

“A few colors of baby poop, should you see them, always warrant discussion with your baby's doctor. ... In any case, any amount of bloody poop should be evaluated because it can be a sign of a problem.” American Academy of Pediatrics

“Black-colored poop is worth paying attention to because blood typically turns from red to black over time in the intestinal tract. Remember that this black color alert does not apply to your baby's first few meconium bowel movements, which you can fully expect to be black and tarry looking without having to be concerned about blood.” American Academy of Pediatrics

“White poop is quite rare but needs to be brought to the attention of a doctor as soon as possible. Pale poop that's lacking in color can be caused by an underlying liver problem.” American Academy of Pediatrics

“By day 5, passing black or dark green stools is not normal. Your baby should be seen to make sure your baby is getting enough milk.
Normal Breastmilk Stools without any meconium present are seen from day 5 on. The stools are runny, mustard-colored and can contain seedy particles.” AAP KidsDoc (Barton Schmitt, MD)

“In the first week after birth, you may see a pink or brick-red stain on the diaper, often mistaken for blood. In fact, this stain is usually a sign of highly concentrated urine, which has a pinkish color. As long as the baby is wetting at least four diapers a day, there probably is no cause for concern. If the pinkish staining persists, consult your pediatrician.” American Academy of Pediatrics

“If you notice a definite change of any kind, such as the poos becoming very smelly, very watery or harder (particularly if there's blood in them), you should talk to your doctor or health visitor. If your baby's poos look pale, this can be a sign of jaundice. Speak to your health visitor or GP if you notice this.” NHS

“Ask for an urgent GP or midwife appointment or call NHS 111 if: ... Your baby is over 24 hours old and: ... their poo is a pale creamy colour (keep a sample of poo to show a midwife or doctor)” NHS

“If your baby has jaundice and also has pale yellow, white or grey poo, see your GP immediately – this can be a sign of a rare liver disease.” Raising Children Network