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)
Youth Small (6-8) - Charcoal1723
Youth Medium (10-12) - Charcoal17.524
Youth Large (14-16) - Charcoal1825
Youth XL (18-20) - Charcoal19.526.5