Chest: Measure all around your chest just below your armpits.
Waist: Measure round your waistline, where your trousers would button up.
Height: Your natural height
If you fall between the sizes, go for the larger of the two.
Measurements are in inches.
Unisex cotton t-shirt
XS 5'6" height, 34" chest, 28" waist
S 5'8" height, 37" chest, 30" waist
M 5'10" height, 39" chest, 32" waist
L 6'0" height, 41" chest, 35" waist
XL 6'2" height, 46" chest, 39" waist
2XL 6'4" height, 51" chest, 44" waist
3XL 6'4" height, 53" chest, 47" waist
4XL 6'4" height, 56" chest, 51" waist
5XL 6'4" height, 60" chest, 54" waist
Oversized cotton t-shirt
XS 34" chest, 28" waist
S 37" chest, 30" waist
M 39" chest, 32" waist
L 41" chest, 35" waist
XL 46" chest, 39" waist
2XL 51" chest, 44" waist
Kids cotton t-shirt
3-4 years 39" height, 24" chest
5-6 years 44" height, 26" chest
7-8 years 49" height, 28" chest
9-10 years 54" height, 30" chest
11-12 years 58" height, 33" chest