👟 Brand to Brand
On to Nike Shoe Size Conversion
Switching from On to Nike? On runs true to size and Nike runs small, so the size you order changes. Here's the full chart.
A On 9 works out to a Nike 9.5 — about half a size up. The chart below has every size.
On → Nike: size up half a size
A On 9 is a Nike 9.5.
Find your On size on the left, read across for Nike:
| On size | Nike 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. Nike tends to run about half a size small — most people size up half, and lifestyle models (Air Force 1, Blazer) run especially snug.
Nike to On → · On chart · Nike chart · Brand finder
What is a On 9 in Nike?
A On 9 is about a Nike 9.5 — they share a foot length of roughly 26.3 cm (UK 8, EU 41.5).
Do On and Nike fit the same?
No — On runs true to size and Nike runs small, so size up half a size when you switch.
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