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 17.5028
Adult Medium 1828
Adult Large 20.5029
Adult XL 22.5029.50
Adult 2XL 24.5031.50
Adult 3XL 26.5033.50