Size Chart

 Size Height Weight
OS (One Size) Up to 23" Up to 12 lb
PRE (Preemie) Up to 18" Up to 5 lb
NB (Newborn) Up to 21" 5-8 lb
0-3M 21.5-23" 8-12 lb
3-6M 23.5-26" 12-16 lb
6-9M 26.5-28" 16-19 lb
9-12M 28.5-30" 19-22 lb
12-18M 30.5-32" 22-27 lb
18-24M 32.5-34" 27-30 lb
2T 34.5-35" 28-30 lb
3T 35.5-37" 30-33 lb
4T 37.5-40" 33-36 lb
0-6M 18-26" 5-16 lb
6-12M 26-30" 16-22 lb