Baby Size Chart Clothes by Age or Height – Boys & Girls

We analyzed hundreds of clothing items from various brands, conducting thorough research to produce detailed size charts. Learn about our methodology and laboratory.

One of the challenges of beginner parenting comes in the seemingly mundane topic of baby clothes sizes. Sizes can be confusing for adult wearers, how much more for babies? Don’t fret, we are about to make it simpler for you! From newborn stage to toddlerhood, here’s the ultimate guide to baby size charts.

Baby clothes size chart: from newborn to toddlers

SizeHeightWeight (lbs)
PreemieUp to 17Up to 5
Newborn17-1/2 - 215-1/2 - 7-1/2
0 - 3M20-1/2 - 236-1/2 - 12
3 - 6M23-1/2 - 2612-1/2 - 16
6 - 9M26-1/2 - 27-1/216-1/2 - 19
12 Month28 - 29-1/219-1/2 - 22
18 Month30 - 31-1/222-1/2 - 26
24 Month32 - 33-1/226-1/2 - 30
2T32 - 33-1/226-1/2 - 30
3T34 - 37-1/230-1/2 - 34
4T38 - 41-1/234-1/2 - 38
5T42 - 44-1/238-1/2 - 42

At a Glance

  • Baby clothes sizes can be determined by the age and weight of the baby. Keep in mind, however, that babies grow and develop at different rates. Different brands also slightly differ in sizes.
  • As a general rule of thumb, buy only grow-suits and singlets in size 0000’s. You can buy more type of clothes in size 000’s to size 1’s since they will be used by the infant for longer.
  • If your baby is walking and potty-trained, you have now graduated to toddler sizes (size 2T and up), which are designed to accommodate your child’s added mobility.
  • While the European sizing for babies is based on height, which is measured in centimeters, UK sizes are more similar with US sizes though with small differences.
Set of clothing and items for a baby

How to measure your Baby’s size

To accurately determine the size of clothing your baby needs, focus on three crucial measurements: chest circumference, hip width, and length from head to toe. Here’s a simplified guide:

  • Chest: While your baby is lying on their back, measure around the chest at its fullest part, which is just below the arms.
  • Hips: With your baby’s feet together, toes pointing up, and legs straight, wrap the measuring tape around the hips at their widest point.
  • Height: Measure your baby from the top of their head to the bottom of their feet while they are stretched out flat.

A flexible tape measure is the best tool for these measurements. You might find it helpful to have someone assist you, either by holding the baby in position or by writing down the measurements. For the most accurate results, especially when measuring height, it’s advisable to do this with your baby wearing minimal clothing or even without a diaper.

In addition to these physical measurements, it’s essential to consider your baby’s weight, which is a significant factor in determining the right clothing size. Clothing sizes for babies from newborns up to 12 months old are often marked according to the baby’s age in months. Yet, these age-based sizes are just starting points. For instance, ‘Newborn’ (NB) sizes suit babies under 7 lbs, and ‘0-3 months’ are designed for those approximately 8-10 lbs. Remember, babies grow at varying rates, and clothing brands may have their unique sizing standards, making it crucial to consult the brand’s specific size chart whenever possible.

Tips to Find the Right Baby Clothes Size

Determining your baby’s clothing size is only one of the few key considerations when it comes to clothing your baby. Here are some additional tips to help you make smarter and more efficient choices:

  • For infants, go for the more practical choices. This means buying quality vs. quantity. You won’t need many baby clothes at this point, as your baby grows quickly during this stage. Additionally, newborns don’t really get their clothes dirty, so they will wear and tear longer. Also, consider buying more gender-neutral clothes, especially if you’re buying before your baby is born.
  • Don’t get too overexcited and buy too many clothes ahead of time. This is a mistake so many newbie parents make too often. Some babies are born big and could only use newborn sizes for a short time. Growth spurts are also very common at this stage. So, it’s important not to buy too much too soon.
  • Always consider your baby’s comfort when choosing clothes. Babies don’t like clothes that have to be pulled over their heads, so avoid separates. Onesies are your best friend.
  • Also consider your comfort as a parent, avoid complicated clothes that will be hard for you to put on your baby.
  • Buy one size ahead of your baby’s age so they can grow in them. This will also help you spend less on clothing.
  • Buy clothing with simpler fastenings. Pants or leggings with elastic waistbands are ideal, and you should avoid anything with buttons or anything that your baby can loosen up. They are very curious during this age and accidents can happen.
  • Anything in cotton will go a long way to making your baby feel more comfortable in clothing, and can also avoid irritation. Materials that are stretchable can also fit your baby longer as they grow.
  • For toddlers, pick more durable clothing. They tend to move more at this age and are prone to damaging their clothes more often.

Following these simple steps and guidelines will not only save you a lot of money along the way but also a lot of time. Dressing your baby can be a great joy you can experience without making any mistakes or having any hassle. Hopefully, this guide has helped you avoid both.

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