Under Armour Boys Size Chart

Baby & Toddler
Size Height Weight Chest Waist Hip Inseam Torso
0/3m 23-25" 8-12 lbs. 16-17" 16.5-17.5" 17-18" 6.5" 23-25"
3/6m 25-27" 12-16 lbs. 17-18" 17.5-18.5" 18-19" 7.5" 26-28"
6/9m 27-29" 16-20 lbs. 18-19" 18.5-19.5" 19-20" 8.5" 29-31"
12m 29-31" 18-22 lbs. 18-19" 18.5-19.5" 19-20" 9.5" 30-31"
18m 31-33" 22-26 lbs. 19-20" 19.5-20.5" 20-21" 11" 32-33"
24m 33-35" 26-30 lbs. 20-21" 20.5-21.5" 21-22" 12.5" 34-35"
2T 33-35" 29-33 lbs. 20-21" 20.5-21.5"      
3T 35-38" 32-36 lbs. 20.5-21.5" 21-22"      
4T 38-41" 35-39 lbs. 21.5-22.5" 21.5-22.5"      
5T 41-44" 38-42 lbs. 22.5-23.5" 22-23"      
Little Boys 4-7
Size Height Chest Waist Hip
4 38-41" 21.5-22.5" 21.5-22.5" 22.5-23.5"
5 41-44" 22.5-23.5" 22-23" 23.5-24.5"
6 44.46.5" 22.5-23.5" 22.5-23.5" 24.5-25.5"
7 46.5-50" 24.5-26" 23-24" 25.5-26.5"
Big Boys 7-16
Size   Chest Waist Hip
XS 7 25-26" 23-24" 26-27"
S 8 26-27" 24-25" 27-28.5"
M 10-12 27-29" 25-27" 28.5-31"
L 14 29-31" 27-28.5" 31-32.5"
XL 16 31-32.5" 28.5-30" 32.5-34"
Husky Big Boys 8-20
Size Height Waist Hip
8H 50-52" 26.5-27.5" 29.5-30.5"
10H 53.5-55.5" 28-29" 31-32"
12H 56.5-58.5" 29.5-30.5" 32.5-33.5"
14H 59.5-61.5" 31-32" 34-35"
16H 62-64" 32.5-33.5" 35.5-36.5"
18H 64.5-66.5" 34-35" 37-38"
20H 67-69" 35.5-36.5" 38.5-39.5"

Size chart is a general guide. It may include sizes that are unavailable for this item.