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 Medium - Royal Blue1929.5
Adult Large - Royal Blue2129.5
Adult XL - Royal Blue22.530.5
Adult 2XL - Royal Blue2532.5