How do you know when it’s time to go up a nappy size?

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Baby looking at nappy

Most nappy brand's sizes, based on your baby’s weight, are pretty accurate. But because, like adults, babies come in all shapes and sizes, this is not always the case.

Here are some signs that you might need to go up a size…

Check the tapes!

When you’re securing your baby's nappy, if the sticky fastening tabs don’t quite reach the centre of the waistband, the nappy is too small! For the perfect fit, the nappy should be snug but you should be able to comfortably fit two fingers under the waistband of the fastened nappy.

On your marks

Whatever type of nappy your baby is wearing, it shouldn’t cause any red marks on your baby’s delicate skin.  If you do spot red marks on your little one’s thighs or tummy, the nappy is probably too small – especially if your baby shows any signs of discomfort when wearing their nappy, or even tries to remove the nappy.

Bum deal

baby bottom

Babies’ bottoms are cute and peachy, but your nappy should cover the entirety of it! If it doesn’t fit, try a bigger size to prevent leaks and discomfort.

 No soggy bottoms!

Many nappies, such as Pura’s, use the latest technology to provide a leak free experience for up to 12 hours. If this is not the case, or if your baby regularly gets nappy rash, it may be because the nappy is too small and doesn’t keep the moisture away from the skin. A bigger size may solve the problem and ensure your little cherub stays comfy and dry.  

 Size matters


As well as being kinder to the planet, Pura’s nappies are designed to keep your baby ultra bumfortable! Check out our Nappy Weight Size Guide to find the best nappy for your growing little wriggler.


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