Newborn Nappies (Diapers): Sizes, Types and How to Choose

Nappies or diapers? The words, and what they mean

In Australia, New Zealand and the UK the word is nappy. In the US and Canada it is diaper. They are the same product, and the choices are the same: disposable or cloth, which size, and how to get a good fit. Most of the advice below applies anywhere. Where a number comes from an Australian or UK health source, the text says so.

Disposable or cloth?

Pregnancy, Birth and Baby describes disposables as designed for one use and then thrown away. It says cloth nappies are generally kinder to the environment and can save money over the long run, but they take more time to wash, some fabrics dry slowly and they cost more upfront. The NHS also says disposables are convenient, while cloth nappies usually cost less across the years a baby wears nappies.

You do not have to pick one for good. Pregnancy, Birth and Baby notes that many parents switch between types as their baby grows, depending on travel, laundry access, bin access and cost. Some cloth brands and councils offer trial packs or samples, and the NHS mentions that a nappy laundry service can collect dirty cloth nappies and deliver a fresh batch each week.

Cloth nappy care. The NHS says cloth nappies can be machine washed at 60°C, but follow your nappy maker's instructions for temperature and detergent. The NHS also advises against fabric conditioner because it makes them less absorbent. It also notes that fabric conditioner can lead to nappy rash. Fitted nappies need a leak-proof cover, according to Pregnancy, Birth and Baby.

How many nappies will a newborn use?

A lot. The NHS says young babies may need changing as many as 10 or 12 times a day, and older babies about 6 to 8 times. At 10 changes a day, that is around 70 nappies a week. Babies do 2 or more poos a day in the first week, and formula-fed newborns may poo up to 5 times a day, the NHS says.

Frequency is not the same for every baby. Pregnancy, Birth and Baby says it depends on how often your baby wees and poos and how they feed, and suggests changing every 3 to 6 hours or straight after a poo. Do not treat that as an interval to wait out: change a wet or soiled nappy promptly, because prolonged contact can make skin sore and red. The Royal Children's Hospital (RCH) gives a lower figure of roughly five to seven changes a day for babies under 12 months, which is a reminder that these are ranges, not rules.

Nappies as a feeding check

Queensland Children's Health uses nappy output to show whether a breastfed newborn is getting enough milk. The figures below are a guide only, and the fact sheet says wide variation is normal.

If wee is pink or orange after day 3, or green-black poo is still present on day 5, the fact sheet says to contact a child health nurse or GP, because it can be a sign of poor feeding. See also our newborn feeding gear guide and formula feeding guide.

Nappy sizes explained: sizes 0, 1, 2 and up

Nappy sizes are set by weight. Brands use different labels: numbers (0, 1, 2, 3), or names such as Newborn, Infant, Crawler, Toddler and Walker. The table below is an illustrative guide, not a universal standard. It lines up the usual sizes with typical weights, who wears them and roughly how long an average baby is at that stage. Length is shown for orientation only, because no brand we checked sizes by height. Those figures come from the World Health Organization (WHO) growth standards, which the BabyQuil growth calculator uses, and individual babies vary.

Where the numbers come from. The weights are the ranges published by Huggies and BabyLove in Australia and by Pampers in the UK. The ages come from the Australian brand Ecoriginals, which publishes approximate ages. Treat everything as approximate: brands overlap and change their ranges, so the same baby can be a different size in different brands.

Which size first? The WHO median birth weight is about 3.3 kg for boys and 3.2 kg for girls, and most healthy babies are born between about 2.5 and 4.3 kg. So most newborns start in the newborn size (size 0 or 1, depending on the brand). Pampers notes that a larger baby may not need size 0 at all, and suggests size 2 for a baby of around 4 to 5 kg. If your baby is between sizes, check the fit rather than the label alone.

• Sizes follow weight, not age. The label on the pack gives a weight range. Ranges overlap and differ between brands, so a size 1 in one brand may not fit like a size 1 in another.
• Newborn size is short-lived. Babies can outgrow it within weeks, so start with a small pack rather than a stockpile. That also lets you try a second brand if the first one leaks.
• Cloth sizing is different. Pregnancy, Birth and Baby says modern cloth nappies use elastic, Velcro or press studs, and most can be adjusted as the baby grows, typically fitting from about 4 to 5 kg until toilet training. A smaller baby may need a newborn-size cloth nappy, so check the maker's range.
• Age is only a rough guide. A big baby may be in the next size early, and a small baby may stay in newborn size longer. Use the pack's weight range and the fit checks below.

How to check the fit

The Absorbent Hygiene Product Manufacturers Association (AHPMA), an industry body, suggests sliding two fingers under the waistband: if you cannot, the nappy is too tight. A good fit generally looks like this:

• Snug, not tight. It sits comfortably at the waist and legs, and you can slide two fingers under the waistband.
• Full coverage. It covers the whole bottom, and the leg cuffs sit around the thighs with no gaps.
• No red marks. Red marks on the tummy or tops of the thighs can mean the nappy is too tight.
• Tabs stick. For disposables, the NHS says to keep water and cream off the sticky tabs, or they will not stick.

Time to size up? According to the AHPMA, consider moving up if the nappy does not cover the bottom, leaves red marks, or your baby has nappy rash. If leaks are the only problem, try a more absorbent nappy in the same size first.

The first weeks: cord stump, meconium and little bodies

• Cord stump. Queensland Children's Health says that if the weather is not cold, you can fold the nappy below the stump so it can air-dry. Use plain water only, pat it dry and do not pull on it. It usually falls off by itself in 7 to 14 days. Some newborn nappies have a notch cut for the cord, which can help, but folding down works for any nappy.
• First poo. The first poo, called meconium, is sticky and greenish-black, says the NHS. After a few days it usually turns yellow or mustard. Breastfed babies' poo is typically runny, and formula-fed babies' is firmer and darker.
• Boys. Pregnancy, Birth and Baby suggests keeping the penis pointed down during changes, and not pulling back the foreskin if present.
• Girls. Wipe from front to back to lower the risk of infection.
• Wetness indicator. Many disposables have a line that changes colour when wet. It is a handy extra, but you can also check by feel and by looking.

How to buy: a simple plan

1. Pick a starting type. Disposable, cloth, or a mix. You can change your mind.
2. Buy one small pack of newborn size. Check the weight range on the pack, and compare it with your baby's weight, or your hospital's estimate if you are still pregnant.
3. Have the next size on hand. Many babies move up within weeks, and it is easier to have one pack ready than to dash to the shop at night.
4. Look at what the pack says. Weight range, absorbency, any fragrance or lotion, and whether it has a cord notch or wetness line. If your baby's skin is sensitive, a plain, fragrance-free option is a sensible place to start.
5. Compare the cost per nappy, not the cost per pack. Pack sizes differ.
6. Use trial packs or samples to test brands before you buy in bulk, including cloth trials from brands or councils.
7. Stock the extras. Barrier cream, cotton wool or fragrance-free wipes, a change mat, a bag for waste, and spare clothes.

Changing a nappy, step by step

The NHS describes a simple routine:

1. Wash your hands and gather everything in one place: a mat or towel, cotton wool and warm water or fragrance-free wipes, a bag for waste, barrier cream, a clean nappy and clean clothes.
2. Change your baby sitting down, on a mat on the floor if possible, so they cannot fall. Never leave them unattended on a changing table.
3. If the nappy is dirty, use it to wipe off most of the poo first.
4. Clean the whole nappy area, including the skin folds, with cotton wool and warm water or wipes.
5. If it is warm enough, let your baby go without a nappy for a while. Otherwise, pat them dry.
6. Apply barrier cream and fit the clean nappy. For cloth nappies, add a liner and fasten it snugly.
7. Wash your hands again.

Disposal. For disposables, the NHS says to roll up the used nappy, reseal it with the tabs, bag it and put it in an outside bin. Pregnancy, Birth and Baby warns that nappy disposal bags are a suffocation risk, so keep them out of your baby's reach.

Nappy rash: prevention and treatment

The RCH says nappy rash is caused by constant moisture from wee and poo plus friction, and that bacteria, yeast, detergents or wipes can make it worse. Most nappy rash clears within a couple of days with barrier cream and good care.

• Change promptly when wet or soiled, and do not leave a nappy on for long stretches.
• Clean gently. Warm water and cotton wool is simplest. If you use wipes, pick fragrance-free ones.
• Use barrier cream. The RCH recommends a thick barrier cream, such as zinc paste, at each change.
• Give nappy-free time. A little each day, when it is warm enough, helps the skin dry.
• Skip powder. Pregnancy, Birth and Baby says to avoid powder on the nappy area.
• Rinse cloth nappies well, and avoid fabric conditioner.

Common mistakes with newborn nappies

1. Buying too many newborn-size nappies. Babies often outgrow them within weeks. Buy small and check weight ranges.
2. Choosing by age alone. Sizes follow weight, and brands differ.
3. Going up a size only when leaks start. Check the fit first. Red marks, gaps around the legs, or a nappy that does not cover the bottom are earlier signs.
4. Fastening too tight. You should be able to slide two fingers under the waistband.
5. Covering the cord stump. Keep it dry and fold the nappy below it so air can reach it, unless the weather is cold (Queensland Children's Health).
6. Leaving a wet nappy on. Prolonged contact makes skin sore and red.
7. Using powder or perfumed products. Water and a barrier cream are the usual advice.
8. Wet tabs. Cream or water on the sticky tabs stops them sticking.
9. Leaving the baby on a change table. Never leave a baby unattended on one.
10. Fabric conditioner on cloth nappies. It reduces absorbency.

The confusing bits, answered

Is "newborn" the same as size 0 or size 1?

Not always. Brands name and size their ranges differently, so go by the weight range printed on the pack rather than the name.

Do I need newborn size at all?

Not necessarily. Some babies fit into the next size from birth, and some are in newborn size for weeks. A small pack is a good compromise.

Are expensive nappies better?

Not by default. The right fit and the right absorbency for your baby matter more than the price. Compare the cost per nappy, and try a sample before you commit.

Are wipes safe on a newborn?

Many health sources prefer water and cotton wool at first. The NHS says you can use cotton wool with plain warm water, or fragrance-free and alcohol-free baby wipes. The RCH advises avoiding baby wipes when treating a rash. If your baby has sensitive skin, water is the simplest option.

Does a nappy cause nappy rash?

It can contribute, because moisture and friction irritate skin. The RCH notes that good-quality disposable nappies are recommended for managing rash because they absorb moisture better than cloth. Cloth users can still prevent rash with prompt changes and thorough rinsing.

How do I know whether my baby is drinking enough from the nappies?

Use the table above as a rough guide for breastfed babies, and speak with a child health nurse, lactation consultant or GP if something looks off or you are unsure.

Frequently Asked Questions