There is not a size on it ...... its all adjustable. But I would say for a small to medium. Right now I have it adjusted to 9" around the neck and 16" around the body. Thanks for asking.
@Kathymorehouseharrison : Okay what I can see from playing with it the around the neck part adjusts at the same time as the body part. My baby girl is 8 pounds and it fits her. But you can make it smaller........ I have it at the largest size.