My 6-Month Old Is Too Big For 12-Month Old Clothes: Should I Be Concerned?

All babies grow at different rates! There are a couple of reasons that can explain why your baby isn’t fitting into clothes recommended for their age.

As adorable as baby clothes are, they can be equally confusing! If you are a new parent especially, we wouldn’t blame you if you felt like there should be a course called Baby Clothing Sizes 101. First of all, there’s size 0 but don’t forget that that’s not the same thing as newborn-size. And then even when you buy the right size (3 months, for example) for your 3-month-old baby, the onesie might end up being way too large or extremely tiny. What gives?

But if your 6-month-old is too big for 12-month-old clothing let alone 6-month-old clothes, is there a reason to worry? We mostly get concerned when babies don’t seem to get bigger but is there such a thing as growing too much? Or is it just baby clothing size confusion? We discuss this down below!

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One Brand Does Not Conform To All

Just like with adult clothing brands, different baby clothing brands can run small or large and fit babies differently. According to, a great example of different brands fitting sizes differently is Baby Gap and Carter. Both are very popular baby clothing brands but Baby Gap’s 3-month-old to a 6-month-old range of clothing can fit babies who weigh 12 to 17 pounds and are 23 to 27 inches tall whereas Carter’s 3-month-old baby clothing fits babies who weigh 9 to 12.5 pounds and are 21.5 to 24 inches tall. Carter’s 6-month-old clothing is made to fit babies who weigh 12.5 to 17 pounds and are 24 to 27 inches tall. This adds up to a big difference.

When brands size and label clothes differently, it can be hard to buy the right size. This can make things especially difficult for moms who have friends and family who want to gift baby clothing. Our advice? Find a brand or two that work perfectly for your baby and stick with it. Politely inform friends and family that Brand X or Brand Z are the best fit for your kiddo if a gift occasion happens to be around the corner.

Blame The Dryer

Clothes really can shrink in the dryer! And since most baby clothes are made out of cotton or organic cotton, it’s little wonder that baby clothes shrink. Many parents like to wash baby clothes in hot water to sanitize dirty or soiled clothes but hot water shrinks cotton so baby clothes should be washed on a cold water cycle. Consider line-drying baby’s clothes or drying them on a low or no-heat setting to fully prevent clothing shrinkage.

Babies Grow Fast (And Differently)

Just because your nephew was able to perfectly fit in his clothes at every baby stage doesn’t necessarily mean that there’s anything wrong with your baby son who is outgrowing his clothes by the minute. According to, babies commonly triple their birth weight and increase their length by 50 percent on average during year 1. By the time babies are 2 years old, they typically gain around 4 inches of length will continue to grow around 3 more inches per year until age 5.

Per NCBI, breastfed babies tend to grow more quickly than nonbreastfed babies during the first six months of life but then nonbreastfed babies typically grow faster than breastfed babies during the second six months of life. That’s a lot of growth – and a lot of clothes!

Keep Track At Your Baby’s Well-Child Visits

Your baby should be regularly weighed and measured at every doctor’s appointment, including the regularly scheduled wellness visits or check-ups. According to NCBI, babies should be weighed and measured: within 1 to 2 weeks of birth, and at 2, 4, 6, 9, 12, 18 and 24 months of age. It’s a great idea to keep your own records of your child’s growth as well. If your child’s growth is normal, their head circumference, weight, and length should follow the same growth pattern over a period of time. If anything seems off to your records, be sure to ask your child’s pediatrician about your concerns.

Buy Bigger Clothes

One money-saving “hack” that some parents choose to use is to simply buy baby clothes in a couple of larger sizes that their child needs so that they can grow into them. Of course, you want to make sure that the clothes are not too loose or baggy as to where they might become a safety hazard.

Of course, if you have any questions about your baby’s growth, make sure to check in with your pediatrician who will be able to put your mind at ease!

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Sources:,, NCBI

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Most Popular European Baby Names Used By American Mothers

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