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)
Adult Small - Royal Blue1627.75
Adult Small - White16.0027.75
Adult Medium - Royal Blue1828.25
Adult Medium - White1828.50
Adult Large - Royal Blue2029.5
Adult XL - Royal Blue20.7530.25
Adult XXL - Royal Blue2531