Newborn vs. Size 1 Diapers: Which Size Should I Buy?

by Julie Siewert September 20, 2019

Newborn vs. Size 1 Diapers: Which Size Should I Buy?

When you are pregnant and thinking ahead to diapers, many new moms ask the question “should I buy newborn or size 1 diapers?”

The answer can be different for everyone, so let me give you some background on diaper sizing…


Newborn diapers

Most standard newborn diapers are designed to fit babies up to 10lbs. But, as we know, all babies are different and each diaper brand can fit a little differently also.

Most newborn diapers do have an umbilical cord cut-out, a small “dip” in the front of the diaper where a baby’s umbilical stump usually is. This is not a “necessary” feature in a diaper (some diaper brands do not have it), but it is convenient so that the diaper does not rub against the umbilical stump.

Most hospitals stock Newborn size diapers for new babies. Most babies when they are born use Newborn diapers.


Newborn vs. Size 1 Diapers - Image of baby changing table

Size 1 diapers

Most standard size 1 diapers are designed to fit babies 8-14lbs. But, as we know, all babies are different and each diaper brand can fit a little differently also.

Size 1 diapers generally do not have the umbilical cut-out, but diapers can be folded down if the baby’s umbilical stump is still present.

Some larger babies start wearing size 1 diapers from birth, so many hospitals do have size 1 diapers available.


Diaper Size Chart for babies

What size diaper will my baby wear?

Did you see the size overlap between the newborn and size 1 diapers? If newborn diapers are designed for babies under 10 pounds, and size 1 diapers are designed for babies 8-14 pounds, then what size diaper does an 8 or 9 pound baby wear? The answer is, maybe both.

Many experienced Moms will recommend only buying a few newborn diapers (if you haven’t already gotten them as gifts), but more size 1 diapers. Because you just don’t know how big your baby will be at birth, or how fast they will grow.


What size Diaper Sampler Packages do parents buy?

If you’re planning ahead and looking at a Diaper Sampler Package, the most common size to buy is size 1. And here’s why:

-Not every baby is born into a newborn size. Some parents (and gift-givers) believe it’s better to have to wait a little bit to use a Sampler Package instead of running the risk they may be too big for it at birth.

-Not every diaper brand is available in a newborn size. Did you know that Costco’s Kirkland Supreme diapers start at size 1?

-Newborn babies are hard. Think back, how much do you remember about that first month at home with your newborn? Me, not much. It was pretty foggy from the sleep deprivation and adjustment period. Some new parents aren’t up for making many extra decisions during those first days with their newborn and prefer to wait until they’re a little more ready to try and compare a variety of diaper brands side-by-side.

 Shop Size 1 Diaper Sampler Packages


Every baby is different

With all the guidelines and best guesses that diaper manufacturers make, every baby is unique. All these weight guidelines are just assumptions based on other babies. Pay attention to the diaper’s fit more than the printed weight range on the diaper package. You’ll know when your baby’s diaper isn’t fitting right and it’s time to switch sizes.

Read more about Diaper Fit



Our most popular gift! The Mega Mom Diaper Sampler Package includes 12 brands of size 1 diapers including eco-friendly and name brand choices.


"What a great idea! Being able to try different diapers before you buy. My baby is transitioning sizes and this let me see which diapers are the next size up but still on the smaller size to fit and also which ones still use the wetness stripe. I definitely now know which are my favorites and future go to's." -Cossandra A.


What IS the difference between newborn and size 1 diapers?

The difference between a newborn “up to 10 pounds” and size 1’s “8-14 pounds” isn’t a lot. But, there is a bit of a size difference as well as some overlap. If your baby is at the smaller end of scale, you might opt for newborn size diapers, but if your baby is closing in on the upper end you might choose to start in size 1's. 

Many babies could really fit in either size (that's where the weight overlap comes in).

As with all things, you’ll want to choose the diaper that works best for your unique baby.


Happy diapering!

Also in Behind the Store

Top Diaper Brands
Top Diaper Brands

by Julie Siewert November 08, 2022

Read More
Which Diaper Brands DO NOT Test on Animals?
Which Diaper Brands DO NOT Test on Animals?

by Julie Siewert October 13, 2022

Read More
Amazon Prime Early Access Sale
Amazon Prime Early Access Sale

by Julie Siewert October 10, 2022

Read More