Gymshark to Decathlon leggings size
The short answer
Gymshark XXS is Decathlon 2XS by the two brands' own charts. 3 of 7 Gymshark sizes land on a different label at Decathlon.
Both brands publish the body waist each size is cut for, so every row matches a waist, not a tag.
| Gymshark | Gymshark builds it for | Decathlon, by chart | Same label | Decathlon builds it for | Decathlon also prints |
|---|---|---|---|---|---|
| XXS | waist 24 in, hip 35.5 in | 2XS | 2XS | waist 23.6 to 24.8 in, hip 31.1 to 33.5 in | not published |
| XS | waist 26 in, hip 37.5 in | XS | XS | waist 25.2 to 26.8 in, hip 33.5 to 35.4 in | not published |
| S | waist 28 in, hip 39.5 in | S | S | waist 27.2 to 28.7 in, hip 35.4 to 37.8 in | not published |
| M | waist 30 in, hip 41.5 in | M | M | waist 29.1 to 31.1 in, hip 37.8 to 40.2 in | not published |
| L | waist 32 in, hip 43.5 in | L | L | waist 31.5 to 33.9 in, hip 40.2 to 42.5 in | not published |
| XL | waist 34 in, hip 45.5 in | L | XL | waist 31.5 to 33.9 in, hip 40.2 to 42.5 in | not published |
| XXL | waist 36 in, hip 47.7 in | XL | 2XL | waist 34.3 to 36.6 in, hip 42.5 to 44.9 in | not published |
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
- Gymshark size guide, read on 2026-09-17. Gymshark on TrueToSize
- Decathlon size guide, read on 2026-09-18.