Baby Diaper Buying Guide

How to pick the perfect size for your baby

by Coterie Team

baby in coterie diaper
baby in coterie diaper

This article does not provide medical advice. The information on site is for informational purposes only. No material on this site is intended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your physician, your child’s pediatrician, or other qualified healthcare providers with any questions you may have regarding your or your child’s health.


With a newborn child, you’ll likely want to choose our newborn diaper size for babies under ten pounds. Our newborn diapers are specifically made with a notch to accommodate the umbilical cord as it slowly fades away. This notch makes the fit more comfortable and less likely to irritate your child.

After the first month, as your child approaches ten to twelve pounds, you’ll want to upgrade to our size one offering. We also offer special mixed packages containing half newborn size and half size one diapers to make sure your child has the perfect fit the moment they are ready.

Changing Sizes

Don’t wait for your child to show signs of discomfort before upgrading to a larger size. Children can grow unexpectedly quickly, so you should check the fit of your child’s diaper once or twice a week.

After securing the diaper, you should be able to easily slip a finger underneath the top of the diaper below your child's belly button. Make sure your finger slides easily from side to side with little resistance. This will also help to ensure you haven’t overtightened the diaper.

Use this same finger trick where your child’s legs come through the diaper. Always make sure the ruffles are on the outside and aren’t folded in. A well-fitted diaper reduces leaks and helps minimize the chance you wake your baby to change their diaper during naps.

For best results, always check the sizing before ordering the next batch of diapers. As your child continues to grow, you can expect them to gain one to two pounds per month until they’re around six months old. Typically, size one will be ideal for one to three months, and size two is good until six months.

Order What You Need

Here at Coterie, our diaper subscription service sends out approximately 190 diapers per box for the first few months. Fewer will be sent out monthly as your child grows and diaper changes become less frequent .

While our packages are designed to last thirty days, some children may use more, while others will use fewer. With this in mind, feel free to set your delivery to every three, four, or five weeks.

We carry seven different sizes, so you’ll always know that we have the right fit for your child. Keep a close eye on the fit of the diaper and always watch for signs of discomfort, such as wriggling, pulling, or trying to remove the diaper. Every child is different, but upgrading in size a little early is better than having leftover diapers that are too small.

Resting in Comfort

When you choose to work with Coterie, you’ll sleep easier knowing that, based on lab testing, our diapers absorb liquids up to four times faster than leading brands. This helps minimize the likelihood of irritation so your baby can be more comfortable. Our diapers are made to very high standards, and both you and your child will love them and the protection they offer!