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Article: Understanding Baby Clothing Sizes and Tips for the Right Fit

Understanding Baby Clothing Sizes and Tips for the Right Fit

Understanding Baby Clothing Sizes and Tips for the Right Fit

We’ve put together our top tips to help you select the right size for your child and ensure you get the most wear out of the gorgeous new items you buy for your little one. Remember selecting the correct size for your baby doesn’t need to be an overwhelming exercise to get right, we're here to help. 

Newborn | Size 0000

For newborns up to approximately 4-6 weeks old, size 0000 is your best bet unless the baby is significantly smaller or larger than average. This size fits babies with a height of up to 56 cm and a weight of up to 3.5 kg. 

We’d recommend packing at least 5-6 of these for the hospital, this is also the perfect size for your special "going home outfit." 

You’ll know it’s time for the next size when your baby's romper is starting to pull down around the neck, there’s no room for stretch across the chest and they’re having a bit of trouble straightening out their legs.

0-3 Months | Size 000

Size 000 is also suitable for newborns who grow rapidly during their first few months. It's best for babies up to 3 months old and a height of 62 cm or less, with a weight of up to 6 kg. 

Milky rompers are designed with lots of stretch for growing bodies to make sure they are comfortable, allowing for movement and growth. 

3-6 Months | Size 00

Size 00 is the typical size for babies aged between 3 to 6 months old. It fits babies up to 8 kg in weight and 68 cm in height. If your baby is in higher percentiles you might want to consider moving up a size. 

Managing your baby’s temperature can be one of the trickiest parts of dressing your child. We recommend dressing them in layers so you can easily add and remove items to achieve the perfect temperature. 

6-12 Months | Size 0

For babies aged between 6 to 12 months old, size 0 is the most common size, providing a broader range of fabric and design options. This size fits babies with a height of 76 cm and a weight of 10 kg. 

Your baby will have more time in this size range and will be starting to sit, crawl and even walk, so you can really start to dress them in cute going out outfits like dresses, jackets and overalls. 

12-18 Months | Size 1

Size 1 is suitable for babies around the age of 1 year old, with a recommended age range of up to 18 months. This size fits babies weighing up to 12 kg and measuring 84 cm. 

Lots of babies will be in a Size 1 before their first birthday so take into consideration the amount of stretch in the fabric or what season you’re wanting them to have it for. ie buying a jacket before the start of winter you might want to buy up a size to ensure they get the full seasons wear out of it. 



Our top tips for selecting the right size: 

TOPS: To get the most wear out of your child's top you can select the next size up and roll up the sleeves while they grow into it. 

PANTS: To ensure your child has room to grow and move in their correctly sized bottoms all of our non-elastic waisted pants have an adjustable elastic inside the waistband to provide the perfect a snug fit. 

We don’t recommend sizing up a whole size in pants, once your child is on the move, as they’ll be too big around the waist and may fall down. 

JACKETS: Layers are the best way to dress your child in colder weather so you can add and remove as needed. With this in mind consider going up a size in your child’s jacket so there’s plenty of room for layers and growth. 


Our final tip is if in doubt go up a size, they will always grow into it. If you’re still unsure feel free to reach out to us, we’d be happy to help guide you in the right direction.

And remember we offer 30 day free exchanges (excluding sale periods) so if it doesn’t fit as you’d hoped we’ll cover the postage cost to get you out the correct size. You can find the full details for exchanges here

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