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 - White Body Black Trim1926.5
Adult Medium - White Body Black Trim19.527
Adult Large - White Body Black Trim20.527.5
Adult XL - White Body Black Trim2228