American Eagle to Gymshark size
The short answer
American Eagle S is Gymshark XS or S by the two brands' own charts. 6 of 9 American Eagle sizes land on a different label at Gymshark.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
| American Eagle | American Eagle builds it for | Gymshark, by chart | Same label | Gymshark builds it for | Gymshark also prints |
|---|---|---|---|---|---|
| XS | chest 35 to 36 in, neck 13.5 to 14 in, sleeve 31.5 in | XS | XS | chest 37 in, waist 29.5 in | not published |
| S | chest 37 to 39 in, neck 14.5 to 15 in, sleeve 32.5 in | XS or S | S | chest 37 in, waist 29.5 in | not published |
| M | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 33.5 in | M | M | chest 41 in, waist 33.5 in | not published |
| M TALL | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 34.5 in | M | not published | chest 41 in, waist 33.5 in | not published |
| L | chest 43 to 45 in, neck 15.5 to 16 in, sleeve 34.5 in | L or XL | L | chest 43 in, waist 35.5 in | not published |
| L TALL | chest 43 to 45 in, neck 15.5 to 16 in, sleeve 35.5 in | L or XL | not published | chest 43 in, waist 35.5 in | not published |
| XL | chest 46 to 48 in, neck 16.5 to 17 in, sleeve 35.5 in | XXL | XL | chest 47 in, waist 39.5 in | not published |
| XL TALL | chest 46 to 48 in, neck 16.5 to 17 in, sleeve 36.5 in | XXL | not published | chest 47 in, waist 39.5 in | not published |
| XXL | chest 49 to 51 in, neck 17 to 18 in, sleeve 36.5 in | XXXL | XXL | chest 49 in, waist 41.5 in | not published |
| XXXL | chest 52 to 54 in, neck 18 to 19 in, sleeve 37 in | not made | XXXL | not published | not published |
What wearers say
Charts describe a garment, not a fit. We do not collect fit reports for this category yet, so this table is the two brands' own claims and nothing more.
Sources
- American Eagle size guide, read on 2026-09-18. American Eagle on TrueToSize
- Gymshark size guide, read on 2026-09-18. Gymshark on TrueToSize