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 - Oxford Grey1826.5
Adult Medium - Oxford Grey19.529
Adult Large - Oxford Grey2129
Adult XL - Oxford Grey2330
Adult 2XL - Oxford Grey25.531