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 - Oxford Grey2028.5
Adult Large - Oxford Grey21.530
Adult XL - Oxford Grey2430.5
Adult 2XL - Oxford Grey2632