GU to lululemon size
The short answer
GU S is lululemon XS by the two brands' own charts. 4 of 6 GU sizes land on a different label at lululemon.
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 | lululemon, by chart | Same label | lululemon builds it for | lululemon also prints |
|---|---|---|---|---|---|
| XS | chest 29.9 to 33.1 in, waist 25.2 to 28.4 in | not made | XS | not published | not published |
| S | chest 31.5 to 34.7 in, waist 26.8 to 29.9 in | XS | S | chest 35 to 36 in | not published |
| M | chest 34.7 to 37.8 in, waist 29.9 to 33.1 in | XS | M | chest 35 to 36 in | not published |
| L | chest 37.8 to 40.9 in, waist 33.1 to 36.2 in | M | L | chest 39 to 40 in | not published |
| XL | chest 40.9 to 44.1 in, waist 36.2 to 39.4 in | XL or L | XL | chest 43 to 45 in | not published |
| XXL | chest 44.1 to 47.2 in, waist 39.4 to 42.5 in | XXL or XL | XXL | chest 46 to 48 in | not published |
| 3XL | chest 47.2 to 50.4 in, waist 42.5 to 45.7 in | XXL or 3XL | 3XL | chest 46 to 48 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.
- lululemon size guide, read on 2026-09-18. lululemon on TrueToSize