👟 Brand to Brand
adidas to On Shoe Size Conversion
Switching from adidas to On? adidas runs small and On runs true to size, so the size you order changes. Here's the full chart.
adidas runs 0.5 size larger than On, so you may need to size down when switching.
Size up 0.5 moving to On
On runs smaller — order half a size larger than your adidas size.
Find your adidas size on the left, read across for On:
| adidas size | On size | UK | EU | Foot (cm) |
|---|---|---|---|---|
| 6.5 | 6 | 5.5 | 37 | 23.5 |
| 6.5 | 6 | 5.5 | 37.5 | 23.9 |
| 7 | 6.5 | 6 | 38 | 24.3 |
| 7.5 | 7 | 6.5 | 38.5 | 24.7 |
| 8 | 7.5 | 7 | 39.5 | 25.1 |
| 8 | 7.5 | 7 | 40 | 25.5 |
| 8.5 | 8 | 7.5 | 41 | 25.9 |
| 9 | 8.5 | 8 | 41.5 | 26.3 |
| 9.5 | 9 | 8.5 | 42.5 | 26.7 |
| 10 | 9.5 | 9 | 43 | 27.1 |
| 10.5 | 10 | 9.5 | 43.5 | 27.5 |
| 11 | 10.5 | 10 | 44 | 27.9 |
| 11.5 | 11 | 10.5 | 44.5 | 28.3 |
| 12 | 11.5 | 11 | 45.5 | 28.7 |
| 12.5 | 12 | 11.5 | 46 | 29.1 |
| 13 | 12.5 | 12 | 47 | 29.5 |
| 13.5 | 13 | 12.5 | 47.5 | 29.9 |
| 14 | 13.5 | 13 | 48 | 30.3 |
| 14 | 13.5 | 13 | 48.5 | 30.7 |
| 14.5 | 14 | 13.5 | 49 | 31.1 |
| 15 | 14.5 | 14 | 49.5 | 31.5 |
⚠️ Fit varies by model. adidas generally runs about half a size small, particularly lifestyle and Ultraboost models; Sambas and Gazelles run long and narrow. On (On Running) runs true to size for most, with a snug, performance fit.
On to adidas → · adidas chart · On chart · Brand finder
What is a adidas 10.5 in On?
A adidas 10.5 is about a On 10 — they share a foot length of roughly 27.5 cm (UK 9.5, EU 43.5).
Do adidas and On fit the same?
Not quite — On runs about 0.5 size smaller than adidas.
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