Last length = foot length + 1.5 cm (between 1 to 2 cm, typically 4⁄3 to 5⁄3 cm, 1.5 cm recommended, different systems are different)
China shoes size (after 1998) = foot length (mm) (EU shoe size is commonly used)
Japan shoe size = foot length (cm)
US male shoe size = 3 × last length (in) − 24 = 3 × foot length (in) − 22
US female shoe size = 3 × last length (in) − 22.5 = 3 × foot length (in) − 20.5
US children shoe size = 3 × last length (in) − 112⁄3 = 3 × foot length (in) − 161⁄3
UK adult shoe size = 3 × last length (in) − 25 = 3 × foot length (in) − 23
UK children shoe size = 3 × last length (in) − 12 = 3 × foot length (in) − 10
EU shoe size = 3⁄2 × last length (cm) = 3⁄2 × foot length (cm) + 2
Female Shoe Size Chart
| Foot Length | China Size | Japan Size | US Size | UK Size | EU Size |
| 21 cm 8.25 in | 210 | 21 | 4 | 2 | 34 |
| 21.5 cm 8.45 in | 215 | 21.5 | 5 | 3 | 34.5 |
| 22 cm 8.65 in | 220 | 22 | 5.5 | 3.5 | 35 |
| 22.5 cm 8.85 in | 225 | 22.5 | 6 | 4 | 36 |
| 23 cm 9.05 in | 230 | 23 | 7 | 4.5 | 36.5 |
| 23.5 cm 9.25 in | 235 | 23.5 | 7.5 | 5 | 37.5 |
| 24 cm 9.45 in | 240 | 24 | 8 | 5.5 | 38 |
| 24.5 cm 9.65 in | 245 | 24.5 | 8.5 | 6 | 39 |
| 25 cm 9.85 in | 250 | 25 | 9 | 6.5 | 39.5 |
| 25.5 cm 10.05 in | 255 | 25.5 | 9.5 | 7 | 40 |
| 26 cm 10.25 in | 260 | 26 | 10 | 7.5 | 41 |
| 26.5 cm 10.45 in | 265 | 26.5 | 11 | 8.5 | 42 |
| 27 cm 10.65 in | 270 | 27 | 11.5 | 9 | 42.5 |
We recommend adopting the size system based on SI units to avoid confusion of choosing shoes and make it easier for people to buy shoes that fit their feet.
