My Cart


What Size Is Best? A Definitive Guide for Dressing Your Child

Posted on February 25 2020

What’s one of the best things about a new baby? The baby clothes of course!

Newborn baby clothes are undoubtedly one of the most fun things to buy for your (or your friend's) little one, but it can be tricky to find the right sizes. Some newborns seem to outgrow everything overnight while others can stick to the same outfit for months. And don’t even get us started on how baby clothes sizes vary from brand to brand.

If you find yourself getting confused and frustrated when it comes to dressing your child, don’t worry! We have all the information you need to understand newborn clothes sizes once and for all.

How to Use A Baby Clothes Size Chart

Baby, Bear, Bed, Blue, Change, Child, Children, Clothes

Most baby clothing will be labelled in a range of months, so you can generally expect your two-month-old to fit into clothes that are for 0-3 month-old children. Right?

Wrong! Maybe your baby is on the larger side and outgrows their clothes more quickly in the early months. Or maybe your little one was born prematurely, and they’ve still got some catching up to do. No baby is exactly the same, so it can be difficult to judge clothing sizes based on age alone.

Instead of relying just on the sizes chart, it’s important to look at baby clothes sizes by weight to ensure proper fit and comfort. Here’s a handy chart to help you decide whether your little one will really fit in that onesie, or if it’s time to make way for roomier options.


Baby Clothes Sizes by Weight and Height

Size (Age Range) Weight Length
00000 (Preemie) Under 2kg Under 55cm
0000 (Newborn) 3kg 55cm
000 (0-3 Months) 3kg – 6kg 55cm – 62cm
00 (3-6 Months) 6kg – 8kg 62cm – 68cm
0 (6-12 Months) 8kg – 10kg 68cm – 76cm
1 (12-18 Months) 10kg – 12kg 76cm – 84 cm
2 (18-24 Months) 12kg – 14kg 84cm – 92cm

How to Pick the Right Newborn Baby Clothes Size

When you’re buying clothes for your newborn, there are a few important things to remember. Don’t be fooled into thinking that one size fits all! The baby's height, weight, and age all factor into the size they can wear. Also, consider:

  • Brand. Certain brands of clothing may run larger or smaller than you think. When in doubt, go one size up to ensure that you’ll be able to get some use out of that cute outfit!
  • Fabric. Some fabrics are stretchier than others, meaning that your baby might fit into that polyester onesie a little longer than those denim trousers.
  • Climate. That sleeveless onesie is cute, but can your newborn wear it in June? To avoid piles of unused clothes, always consider what the temperature will be when the baby is going to wear their new outfit.

Our Tips and Tricks

When it comes to dressing your baby, there’s no one right way for everyone. Choosing clothing sizes based on weight rather than age will be a huge help – not only for you but your baby too! Here are some of our other tips and tricks for getting the most out of dressing your child.

  • Do remember that kids grow fast, especially in the early months! When in doubt, opt for clothing one size larger than you think you need so your child can wear the outfit more often before growing out of it.
  • Don’t put your child in overly large clothing. Imagine how uncomfortable it would be for you if all your clothes were too big!
  • Do choose simple clothing, especially for sleep. Outfits with hoods or other accessories can be dangerous to your little one.
  • Do choose clothing with baby-safe snaps and zippers.
  • Don’t buy too many newborn sizes. We know they’re cute, but babies grow fast!
  • Do keep a few larger sizes of clothing on hand in case your baby goes through a growing stage. Don’t leave clothes shopping to the last minute!
  • Don’t expect sizes to be the same across different clothing brands. What may fit your baby in one brand could be too small in another.

Dress Your Baby for Success

Your little one is relying on you to dress in the right way, and we know that can be a daunting task! Remember that choosing the appropriate clothing sizes is one of the most important elements of choosing the right outfit.

So next time you go shopping, keep our handy size chart in mind. You’ll have an easier time choosing the right baby clothes size to keep your baby happy, healthy, and comfortable.