👟 Brand to Brand
On to adidas Shoe Size Conversion
Switching from On to adidas? On runs true to size and adidas runs small, so the size you order changes. Here's the full chart.
A On 9 works out to a adidas 9.5 — about half a size up. The chart below has every size.
On → adidas: size up half a size
A On 9 is a adidas 9.5.
Find your On size on the left, read across for adidas:
| On size | adidas size | UK | EU | Foot (cm) |
|---|---|---|---|---|
| 6.5 | 7 | 5.5 | 37 | 23.5 |
| 7 | 7.5 | 6 | 38 | 24.3 |
| 7.5 | 8 | 6.5 | 38.5 | 24.7 |
| 8 | 8.5 | 7 | 39.5 | 25.1 |
| 8.5 | 9 | 7.5 | 41 | 25.9 |
| 9 | 9.5 | 8 | 41.5 | 26.3 |
| 9.5 | 10 | 8.5 | 42.5 | 26.7 |
| 10 | 10.5 | 9 | 43 | 27.1 |
| 10.5 | 11 | 9.5 | 43.5 | 27.5 |
| 11 | 11.5 | 10 | 44 | 27.9 |
| 11.5 | 12 | 10.5 | 44.5 | 28.3 |
| 12 | 12.5 | 11 | 45.5 | 28.7 |
| 12.5 | 13 | 11.5 | 46 | 29.1 |
| 13 | 13.5 | 12 | 47 | 29.5 |
| 13.5 | 14 | 12.5 | 47.5 | 29.9 |
| 14 | 14.5 | 13 | 48 | 30.3 |
| 14.5 | 15 | 13.5 | 49 | 31.1 |
| 15 | 15.5 | 14 | 49.5 | 31.5 |
⚠️ Fit varies by model. On (On Running) runs true to size for most, with a snug, performance fit. adidas generally runs about half a size small, particularly lifestyle and Ultraboost models; Sambas and Gazelles run long and narrow.
adidas to On → · On chart · adidas chart · Brand finder
What is a On 9 in adidas?
A On 9 is about a adidas 9.5 — they share a foot length of roughly 26.3 cm (UK 8, EU 41.5).
Do On and adidas fit the same?
No — On runs true to size and adidas runs small, so size up half a size when you switch.
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