How to Find the Right Diaper Size for Your Baby

7 Min Read
baby in bamboo diaper

How to Find the Right Diaper Size for Your Baby

How Do Diaper Sizes Work?

Diaper sizes are determined by how much liquid they are designed to hold, which is why you will see varying sizes across parameters across brands and why your baby may not necessarily be the same size from one brand to another. Because of this, and because ours are sized for maximum absorption, we’ve put together a simple guide to help you determine the right size of Eco Pea diapers to choose for your baby. 

Diaper Size Chart By Weight

To find the right size diaper for your child, check the brand size guide that tells you what size diaper your child will be depending on their weight and then consider the other factors listed below should your child be on the cusp of any size.

Our Eco Pea bamboo diapers and training pants are designed for maximum absorption, so you may find our sizing differs slightly from other brands, note our sizing chart below.

  • Newborn: 10 lbs and under
  • Size 1: 7-17 lbs
  • Size 2: 14-24 lbs
  • Size 3: 21-31 lbs (includes our training pants)
  • Size 4: 28-44 lbs (includes our training pants

How to Know if a Diaper is the Right Fit

Ideally, your child’s diaper will come up to just below their belly button, you’re able to fasten it easily, it doesn’t make marks on baby’s thighs, and it doesn’t easily leak. Another sign that a diaper is the proper size is if you can fit about two fingers into the waist of the diaper when it’s fastened.

How to Know if a Diaper is Too Small 

If you notice that they’re having frequent leaks or blowouts, the top of their bottom is easily exposed, they have red marks around their thighs, or you’re having trouble fastening the straps, it’s probably time to go up a size. A diaper should fit comfortably and allow your child to move about easily, while being snug enough to contain wetness.

How to Know if a Diaper is Too Big

If there seems to be a lot of space between your child’s diaper and their legs, the straps overlap when fastened, or the diaper seems to be leaking more than expected, it’s probably best to move one size down. The nice thing about diapers that are too big is that you don’t have to donate or throw them out, as baby will eventually grow into them.   

When to Change Diaper Sizes

As you can see, there is some overlap between diaper sizes. If your baby is in between weights and you're not sure what diaper size is best for them, you'll want to consider the following:

  • Frequent blowouts and leakage issues? If so, it's time to size up your diapers.
  • Having to tug on tabs to fasten the diaper? Time to move up a size.
  • Red marks appearing on baby's waist and/or thighs? Think about changing sizes.

If you have a diaper subscription with Eco Pea, you can easily change sizing (and even order multiple sizes) within your account to ensure you get the right size, every time. 

What Eco Pea Diaper Size is Best for Your Baby?

Eco Pea diapers are not your average diaper. Designed for maximum absorption, comfort and sustainability, you will find our diapers to feel extra soft and luxurious, while doing the job for both daytime and overnights. Our sizing looks a bit different than other diaper brands because our diapers have been designed to absorb the most liquid, and therefore can fit on the larger side. Fit will vary depending on the child so always refer to our size guide and consider the point above before choosing your diaper size.

How to Figure Out a Child's Weight

Because your child can gain a considerable amount of weight between paediatrician visits, it might be difficult to know their exact weight when trying to determine their diaper size. A trick is to get on the scale and note your own weight, then get back on the scale with your baby. The difference in the two numbers is your baby’s approximate weight. For example, if you get on the scale and you’re 140lbs, and you’re 155lbs when holding your child, then they’re about 15lbs. 

As you try to find the right diaper size, we hope this guide adds ease to a process that can sometimes feel confounding. When you find the sweet spot with diaper size, your parent’s intuition will likely get a ping. Suddenly, it will be simpler to get the diapers on, you’ll no longer be dealing with regular leaks, and above all, your child will express little to no complaints about wearing diapers.