Under Armour Boy's Size Chart

US SIZES CHEST (in) WAIST (in) HIPS (in)
YSM 8 26-27 24-25 27-28½
YMD 10-12 27-29 25-27 28½-31
YLG 14 29-31 27-28½ 31-32½
YXL 16 31-32½ 28½-30 32½-34

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.

HIPS: With your feet together, measure around the fullest part of your hips to ensure you'll have enough room to move comfortably.

Measurements updated Jul2018. For additional sizing information, please go to https://www.underarmour.com/en-us/t/size-guide.html