MUJI to Reformation clothing size
The short answer
MUJI M is Reformation XS by the two brands' own charts. 4 of 4 MUJI sizes land on a different label at Reformation.
Both brands publish the body bust each size is cut for, so every row matches a bust, not a letter or a number.
On 3 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.
| MUJI Japan sizing | MUJI builds it for | Reformation, by chart | Same label | Reformation builds it for | Reformation also prints |
|---|---|---|---|---|---|
| XS | bust 28.7 to 30.3 in, waist 22.1 to 23.6 in, hip 31.9 to 33.5 in | not made | XS | not published | not published |
| S | bust 29.5 to 31.9 in, waist 22.8 to 25.2 in, hip 32.7 to 35 in | not made | S | not published | not published |
| M | bust 31.5 to 33.9 in, waist 24.8 to 27.2 in, hip 34.7 to 37 in | XS | M | bust 33 in, waist 25 in, hip 36 in | US 0 |
| L | bust 33.5 to 35.8 in, waist 26.8 to 29.1 in, hip 36.6 to 39 in | S | L | bust 35 in, waist 27 in, hip 38 in | US 2/4 |
| XL | bust 35.4 to 37.8 in, waist 28.7 to 31.1 in, hip 38.6 to 40.9 in | M | XL | bust 37 in, waist 29 in, hip 40 in | US 6/8 |
| XXL | bust 37.4 to 39.8 in, waist 30.7 to 33.1 in, hip 40.6 to 42.9 in | L or M | not published | bust 39.5 in, waist 31.5 in, hip 42.5 in | US 10 |
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
- MUJI Japan sizing size guide, read on 2026-09-25.
- Reformation size guide, read on 2026-09-18. Reformation on TrueToSize