GU to Banana Republic size
The short answer
GU XS is Banana Republic XXS by the two brands' own charts. 7 of 7 GU sizes land on a different label at Banana Republic.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
On 1 sizes the charts land two or more sizes from the same label. Brands do not measure the body the same way, so on those rows treat the chart answer and the same label as the two ends of a range.
| GU Japan sizing | GU builds it for | Banana Republic, by chart | Same label | Banana Republic builds it for | Banana Republic also prints |
|---|---|---|---|---|---|
| XS | chest 29.9 to 33.1 in, waist 25.2 to 28.4 in | XXS | XS | chest 32 to 33 in, waist 25 to 26 in, neck 13 to 13.5 in, sleeve 31 in | not published |
| S | chest 31.5 to 34.7 in, waist 26.8 to 29.9 in | XXS | S | chest 32 to 33 in, waist 25 to 26 in, neck 13 to 13.5 in, sleeve 31 in | not published |
| M | chest 34.7 to 37.8 in, waist 29.9 to 33.1 in | S | M | chest 36 to 37 in, waist 29 to 31 in, neck 14 to 14.5 in, sleeve 33 in | not published |
| L | chest 37.8 to 40.9 in, waist 33.1 to 36.2 in | M | L | chest 38 to 40 in, waist 32 to 33 in, neck 15 to 15.5 in, sleeve 34 in | not published |
| XL | chest 40.9 to 44.1 in, waist 36.2 to 39.4 in | L | XL | chest 41 to 44 in, waist 34 to 35 in, neck 16 to 16.5 in, sleeve 35 in | not published |
| XXL | chest 44.1 to 47.2 in, waist 39.4 to 42.5 in | XL | XXL | chest 45 to 48 in, waist 36 to 37 in, neck 17 to 17.5 in, sleeve 35.5 in | not published |
| 3XL | chest 47.2 to 50.4 in, waist 42.5 to 45.7 in | XXL | not published | chest 49 to 52 in, waist 38 to 39 in, neck 18 to 18.5 in, sleeve 36 in | 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
- GU Japan sizing size guide, read on 2026-09-25.
- Banana Republic size guide, read on 2026-09-18.