When trying to decide between two sizes, choose the larger size for a better fit.

SizeChestWaistHipsHeightWeight
XS (0-6)18up to 18.518.5Up to 26Up to 16 lbs.
S (6-12)1918.5 - 19.519.526 - 29.516-23 lbs.
M (12-18)19.7519.5 - 20.2520.2529.5 - 3223-27 lbs.
L (18-2T)20.520.25 - 212132 - 3427-30 lbs.
Baby Costume Sizing Chart Diagram