Oofos Size Guide
| Foot Length | US | US | UK | UK | EU | EU |
| 228mm | 3 | 5 | 2 | 2.5 | 36 | 35 |
| 235mm | 4 | 6 | 3 | 3.5 | 37 | 36 |
| 241 mm | 5 | 7 | 4 | 4.5 | 38 | 37.5 |
| 248mm | 6 | 8 | 5 | 5.5 | 39 | 38.5 |
| 254mm | 7 | 9 | 6 | 6.5 | 40 | 39.5 |
| 260mm | 8 | 10 | 7 | 7.5 | 41-42 | 41 |
| 267mm | 9 | 11 | 8 | 8.5 | 43 | 42 |
| 273 mm | 10 | 12 | 9 | - | 44 | - |
| 279mm | 11 | 13 | 10 | - | 45 | - |
| 286mm | 12 | 14 | 11 | - | 46 | - |
| 292mm | 13 | 15 | 12 | - | 48 | - |
| 302mm | 14 | 16 | 13 | - | 49 | - |
| 310mm | 15 | - | 14 | - | 50 | - |
| 318 mm | 16 | - | 15 | - | 51 | - |
| 320mm | 17 | 18 | 16 | 12 | 52 | 48 |
| 322mm | 18 | 19 | 17 | 13 | 53 | 49 |