// Birkenstock Comfort Footwear Size Matrix.
| US Men | US Women | US Kids | UK | EU / Birk | CM / JP | Foot (cm) |
|---|---|---|---|---|---|---|
| - | 4 - 4.5 | - | 2.5 | 35 | 22.5 | 22.5 |
| - | 5 - 5.5 | - | 3.5 | 36 | 23.0 | 23.0 |
| - | 6 - 6.5 | - | 4.5 | 37 | 24.0 | 24.0 |
| - | 7 - 7.5 | - | 5.0 | 38 | 24.5 | 24.5 |
| - | 8 - 8.5 | - | 5.5 | 39 | 25.0 | 25.0 |
| - | 9 - 9.5 | - | 7.0 | 40 | 26.0 | 26.0 |
| - | 10 - 10.5 | - | 7.5 | 41 | 26.5 | 26.5 |
| - | 11 - 11.5 | - | 8.0 | 42 | 27.0 | 27.0 |
| 7 - 7.5 | - | - | 7.0 | 40 | 26.0 | 26.0 |
| 8 - 8.5 | - | - | 7.5 | 41 | 26.5 | 26.5 |
| 9 - 9.5 | - | - | 8.0 | 42 | 27.0 | 27.0 |
| 10 - 10.5 | - | - | 9.0 | 43 | 28.0 | 28.0 |
| 11 - 11.5 | - | - | 9.5 | 44 | 28.5 | 28.5 |
| 12 - 12.5 | - | - | 10.5 | 45 | 29.0 | 29.0 |
| 13 - 13.5 | - | - | 11.5 | 46 | 30.0 | 30.0 |
| 14 - 14.5 | - | - | 12.0 | 47 | 30.5 | 30.5 |
| 15 - 15.5 | - | - | 13.0 | 48 | 31.0 | 31.0 |
| 16 - 16.5 | - | - | 14.0 | 49 | 32.0 | 32.0 |
| 17 - 17.5 | - | - | 15.0 | 50 | 32.5 | 32.5 |
| - | - | 6 - 6.5 | - | 24 | 15.0 | 15.0 |
| - | - | 7 - 7.5 | - | 25 | 15.5 | 15.5 |
| - | - | 8 - 8.5 | - | 26 | 16.0 | 16.0 |
| - | - | 9 - 9.5 | - | 27 | 16.5 | 16.5 |
| - | - | 10 - 10.5 | - | 28 | 17.0 | 17.0 |
| - | - | 11 - 11.5 | - | 29 | 18.0 | 18.0 |
| - | - | 12 - 12.5 | - | 30 | 18.5 | 18.5 |
| - | - | 13 - 13.5 | - | 31 | 19.0 | 19.0 |
| - | - | 1 - 1.5 | - | 32 | 20.0 | 20.0 |
| - | - | 2 - 2.5 | - | 33 | 20.5 | 20.5 |
| - | - | 3 - 3.5 | - | 34 | 21.5 | 21.5 |