Sizes are not standardized in the US and some brands will run larger or smaller, so it’s important to take into account your baby’s height and weight.

There are a few different types of baby clothing sizes, including preemie, newborn, 0-3 months, 3 months and 6 months, 9-12 months, 12-18 months and 18-24 months. Each brand may have their own sizing charts, and even within each group, some brands have their own sizing ranges (for example, Nordstrom caters to bigger babies while Walmart looks for smaller ones).

Newborn Clothes

The newborn clothes size is for baby’s that are born between the week of birth and their first birthday. Generally, it’s for babies who are between 5 and 8lbs and up to 21.5 inches long.

Generally, this is a great size to start with. It will provide a lot of flexibility for the parents, as they can change the pants and sleeves to accommodate the baby’s growth spurts.

A good rule of thumb is to buy a small number of items in this size, so that you can use them until they’re ready for a 0-3 month clothes size. However, it’s not a bad idea to get an outfit that can be used for a couple of weeks in the 0-3 month clothes size as well, just in case they don’t quite grow into the size that you were planning on buying.

You should also know that the sizing for infants in Europe is based on centimeters instead of age. This means that they tend to be smaller than US infants.

0-3 months and 3 months are considered the same in Europe, so you should find that this size is suitable for babies who weigh between 8 and 12lbs and who are between 21.5-24″ in length.

For the 3-6 months clothing size, it’s for babies who weigh between 12 and 18lbs and who are between 24 and 27 inches in length.

It is worth noting that this size is still relatively narrow, so it might be a good idea to shop for items that can be rolled up.

Once the 0-3 months clothing is worn out, it’s time to move on to the 3-6 month clothes size. This will be a good fit for your baby, as they’ll have grown out of the 0-3 month size in a matter of a few months, and it will provide a little more room to grow.

In addition to sizing, you’ll want to consider how the materials in the clothes are made, since certain fabrics can irritate the skin of a growing baby. This can cause red lines on the skin, which can be painful for the baby.

If you’re confused about the sizes, check out our baby clothes size chart for a simple guide to what each size means.

Toddlers

Once your baby is walking and potty-trained, you’ve graduated to toddler sizes (size 2T and up). This is a great time to get some clothing that will be more useful as your little one grows. Unlike newborn and infant clothing, toddler sizes are designed to be more active and allow for added mobility. This is why you’ll see more toddler clothes on the market than infants.