Sizing Charts

Size Age Height Weight
Small 3-6 months up to 28 inches 12-19lbs
Medium 6-12 months up to 32 inches 19-26lbs
Large 12-24 months up to 39 inches 26-34lbs

*size chart
NOTE: Zipadee-Zip ideal fit has slight resistance in the arm span because this is helpful when transitioning a baby off of the swaddle.



The small is geared towards the 12-19 or 20 pound mark and is designed for babies up to 6 months old, or up to 28 inches tall. Some little ones use the small until 22lbs. The length of the zipper alone on all the Zipadee-Zips is 24 inches (remember that a baby’s head makes up a good portion of their height so the small will fit most little ones under that 6 month mark with no problem.

If a caregiver is using the Zippy as a SWADDLE TRANSITION and their little one is around 17-18 lbs and is under 6 months old, I recommend the small to start because there is more resistance in that wing-span which gives the baby more of a feeling of being enclosed and cozy. This womb-like sensation is what helps ease the transition off of the swaddle.

If your baby weighs above 18 pounds and is around 28 inches tall, they are on the cusp of moving to a Medium and may not be in the Small for very long. If you decide to go with a size Medium so that your little one can grow into it, make sure to do nap times in the Zipadee-Zip first for a while before moving to night time sleep. That will help ease your little one into the freedom over a shorter period of time. Ideally you want to have resistance in the arm span if you are transitioning from the swaddle.


If your baby is over 6 months old AND over 18lbs, or over 28 inches tall, go with the medium. Past 6 months old, the startle reflex has started to subside so it’s easier to make the transition off of the swaddle in a slightly larger size as long as your baby is 18 lbs or over. Most babies wear the Medium until 12 months old or older. The medium fits babies up to 32 inches tall.

If the Zipadee-Zip is not being used as a transition solution or is not being used to help improve sleep or self-soothing skills, the resistance in the arm-span is not as important and more freedom in the fit will be just fine!


This size is NOT meant for the transition off of the swaddle but after a baby has already made that transition with a smaller size. I also do not recommend skipping the size Medium and going from the Small to the Large. There is a reason behind how the Zipadee-Zips are sized as it provides a gradual transition to full freedom making the move to PJ’s instantaneous and easy! The difference between a size Medium and a size Large is pretty significant. The Large gives a baby lots of extra room with no resistance at all. This size is also a perfect alternative for parents who haven’t swaddled and just want to put their little ones in a wearable blanket that keeps those little hands warm at night and prevents scratching.