Boys 

	US Sizes	Chest (in)	Waist (in)	Hips (in)	Height (in)	Inseam
YXS	7	25-26	23-24	26-27	47-50.5	21-23.5
YSM	8	26-27	24-25	28.5-31	51.5-55	22-23.5
YMD	10-12	27-29	25-27	28-31	53-59	25-27.5
YLG	14-16	29-32.5	27-30	31-34	59-65	27.5-31
YXL	18-20	32.5-35.5	30-33	34-37	65-70	31-32

Chest: Place the tape measure under your arms at the fullest part of your chest, wrap around your body until your fingers meet and mark the measurement.
Waist: Measure around your natural waistline - right above your hips. Be careful not to squeeze too tight to allow a little give.