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 - Black1827.5
Adult Small - White17.527.5
Adult Medium - Black2028
Adult Medium - White2028
Adult Large - Black21.529
Adult Large - White2229.5
Adult XL - Black22.530.5
Adult XL - White23.531
Adult 2XL - Black2530
Adult 2XL - White25.532
Adult XL - White