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 - Sky Blue1827.5
Adult Medium - Sky Blue19.529
Adult Large - Sky Blue2229.5
Adult XL - Sky Blue2330
Adult 2XL - Sky Blue25.531.5