Width is measured across the chest below the sleeves from seam to seam. Height is measured from the bottom of the shirt to the highest point on the shoulder (where the seam meets the neck).

Please note that each product has its own specific sizing chart.
SizeWidth (inches)Height (inches)
Juvenile 413.5017.50
Juvenile 5-6 - Navy Blue1519.5
Juvenile 715.5020
Toddler 2T - Navy Blue11.514.5
Toddler 3T - Navy Blue12.515
Toddler 4T - Navy Blue13.517