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 Grey19.529
Adult Large - Oxford Grey21.529.5
Adult XL - Oxford Grey23.531
Adult 2XL - Oxford Grey2532
Adult 3XL - Oxford Grey2731.5