A Quick Guide to Baby Clothes Sizing

A Quick Guide to Baby Clothes Sizing

Did you know that there are 3.6 million babies born every year in the United States alone? If you are a new parent or purchasing gifts for someone that has just become a parent, figuring out the right size for baby clothes can be confusing. You might even encounter variations between manufacturers, styles, and even fabric choices. 

From how to measure your baby for the best fit to understanding the different sizing options around, we've collected a quick guide to baby clothes sizing for you so that you can remove the guesswork and make sure you get the right fit for your infant or toddler's wardrobe

How to Measure Your Baby for Baby Clothes Sizing

While it can be difficult to get accurate measurements from a wriggling baby, we’ve put together some helpful tips on how to get it right. 

First off, make sure you have a good flat surface so that you can spread out a blanket to lay your baby on to begin your measurements. Have a flexible tape measure on hand. You'll also want to record the baby's height and weight, which is most accurately done without a diaper. 

Related: A Gift Guide For Personalized Baby Girl Clothes 

With your baby's true measurements, you'll be able to shop with confidence and take advantage of any baby clothes sales. These are the areas you will need to measure:

  • Hip Circumference: For an accurate hip measurement, the baby should be on their back, toes up in the air with straight ankles and feet touching.  Make sure you measure the baby’s hip circumference at the widest part of the hip.
  • Chest Circumference: Put the tape measure underneath the baby’s arms at the widest part of the chest while the infant is on their back to accurately check chest circumference.
  • Arm Length: Hold the baby’s hand and measure from the wrist to the shoulder of the straight arm.
  • Inseam: Accurate inseam measurements are taken from the crotch to the bottom of the foot of one leg.

Taking these measurements means that you'll be able to find clothing to fit your child without any guesswork.

How to Choose the Right Sizing for Baby Clothes

Clothing sizes for newborns or infants is determined using a variety of factors. It may take into account the age or weight, or even length of the child. So to make sure you are buying clothing that will fit your child, there are certain things to bear in  mind:


The type of fabric for your baby's clothes matters. Cotton will be comfortable, but items from some brands—particularly non-luxury ones—may shrink with repeated washing. Babies go through a lot of clothes from day to day, so you will want clothes that are durable and can withstand the laundry process. If you want cotton, consider sizing up when buying from non-luxury brands—or make sure you purchase from a company that creates high-quality cotton baby clothes designed to withstand shrinkage while remaining soft and beautiful, wash after wash.

Trial and Error

If you are buying a lot of different baby clothes brands, you may have to test them all out and see what fits your baby. Sizes vary from company to company. The best way is to have your baby's current measurements on hand and look up each brand's sizing chart to figure out the best match every time you shop.

Research the Clothing 

Some clothing companies tend to run small/large, shrink, not hold up, or worse. By doing research on the company, reading reviews of the clothes, and learning about their fabric and cut, you can make the best decision for your child's long-term clothing needs. Remember, reviews that simply say, "It's cute!" aren't helpful when you're trying to find sizing and durability.

Learn about Labels

You'll want to remember that the size on the tag is an estimate and often the age at which a child will have outgrown the item. Your new footed pajamas that say 6 months may not fit your 6-month-old baby. 

The label gives you an estimate, but your baby may be growing faster or slower than that. By 6 months of age, many children are in 9–12-month clothes. Your baby is growing on his or her own timeline, so adjust the clothes to the baby and don’t worry if the age on the clothes doesn’t match the age of your baby.

RELATED: The Best Baby Shower Gifts For Any Budget 

Learning about baby clothes sizing and the correct way to choose them can help you whether you are buying for your own child, or for someone else's as a gift for birthdays or baby showers.

Baby Clothes Sizing

A general guide to baby clothing sizes is as follows:

  • Premature: 5 lbs and under
  • Newborn: 5-8 pounds
  • 3 Months: 8-12 pounds
  • 6 Months: 12-16 pounds
  • 9 months: 16-20 pounds
  • 12 Months: 20-24 pounds
  • 18 Months: 24-28 pounds
  • 24 Months: 28-30 pounds
  • 2T: 29-32 pounds
  • 3T: 32-35 pounds
  • 4T: 35-39 pounds
  • 5T: 39-43 pounds

Remember that this is a template guide, and actual sizing will vary by company.

Are Your Baby Clothes Too Big? Here's What to Do

Sometimes when you are between sizes baby clothes may be too big for your infant. While this is better than them being too small and constrictive, there are things you can do to make clothes that are too big more comfortable.

  • Hem the clothes: If you are adept with a sewing machine or needle and thread you can alter the clothes to be smaller.
  • Roll them: Rolling the pants or sleeves when they are too long can help them fit better and allow them to easily be fixed when the child does grow into the clothes.
  • Sock the pants/pajamas: If there are pajamas or pants that are footed and are too long to properly fit your child making for excess fabric, you can add socks to the feet over the footed area. This will help keep them in place. Make sure the socks aren't too tight and that the baby isn't too warm with this added clothing.
  • Fold the waist: Some pants may allow you to just fold over a waistband. Flipping the waistband will mean that the legs are shorter and may fit your child better.

While babies should transition between baby clothes sizes with little to no problem, it is not uncommon to dress them in clothes that leave a little room to grow. These tips and tricks can help you make clothing adjustments to ensure a better fit while your baby grows into your new size options.

How Many Baby Clothes Do You Need in Each Baby Size?

When creating your baby's clothing collection, there are some essential items to remember, including onesies, rompers, pajamas and booties. Here's a quick list of the essentials to get in every size:

  • 6 shirts
  • 7 footed pajamas
  • 6 onesies
  • 5 one-piece rompers
  • 3 two-piece outfits
  • 6 socks/booties
  • 2 dressy outfits
  • Summer Babies – a swimsuit and a sun hat
  • Winter Babies – a sweater, snowsuit, and a knit hat

This is a great starting point for the essentials, and you can add or subtract as needed for you and your baby's circumstances. Another fabulous idea? Grab some of these in a monogrammed or other personalized option for gift-giving or to show off your baby's customized style!

Properly Sized Baby Clothes for Every Occasion

Now that you know how to measure your baby, the factors that may influence clothing sizes, and some of the things to look for in baby clothes essentials, you are going to want to go shopping! At Elegant Baby, we know everything there is to know about luxury baby products and offer the best in fashionable baby clothes. Shop the collection today and find personalized baby gifts and high-end blankets, toys and apparel, to delight even the most discerning recipients.

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