Smartwool to Nike leggings size
The short answer
Smartwool S is Nike M by the two brands' own charts. 5 of 5 Smartwool sizes land on a different label at Nike.
Both brands publish the body waist each size is cut for, so every row matches a waist, not a tag.
| Smartwool | Smartwool builds it for | Nike, by chart | Same label | Nike builds it for | Nike also prints |
|---|---|---|---|---|---|
| S | waist 29 to 31 in, hip 36 to 38 in | M | S | waist 29 to 31.5 in, hip 38.5 to 41 in | US numeric 8-10 |
| M | waist 32 to 34 in, hip 39 to 41 in | L | M | waist 31.5 to 34.5 in, hip 41 to 44 in | US numeric 12-14 |
| L | waist 35 to 37 in, hip 42 to 44 in | XL | L | waist 34.5 to 38.5 in, hip 44 to 47 in | US numeric 16-18 |
| XL | waist 38 to 40 in, hip 45 to 48 in | XXL | XL | waist 38.5 to 42.5 in, hip 47 to 50 in | US numeric 20-22 |
| XXL | waist 41 to 44 in, hip 49 to 51 in | 0X | XXL | waist 40 to 43 in, hip 48 to 51 in | US numeric 16W |
What wearers say
Charts describe a garment. People who own both brands describe a fit, and their answer ranks above this table once five of them stand behind it. Pick your size in the converter to see whether there are enough yet.
Sources
- Smartwool size guide, read on 2026-09-18.
- Nike size guide, read on 2026-09-17. Nike on TrueToSize