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 Body Red Trim1928
Adult Medium - Royal Body Red Trim1928
Adult Large - Royal Body Red Trim2028.5
Adult XL - Royal Body Red Trim2130
Adult 2XL - Royal Body Red Trim2431