US Size 6.5=38     fit for foot length is 25cm.

US Size 7=39       fit for foot length is 25.5cm.
US Size 7.5=40     fit for foot length is 26cm.
US Size 8=41       fit for foot length is 26.5cm.
US Size 8.5=42     fit for foot length is 27cm.
US Size 9.5=43     fit for foot length is 27.5cm.
US Size 10=44      fit for foot length is 28cm.