The size is measured by hands, it may has 1-5 mm different.
We send CN size,please refer to your foot length to choose US size.
For example, if my foot length is 27cm, I will choose the US size 9.5 = CN size 44.
If your foot is narrow and thin, you can choose one size smaller.
If your foot is wide and fat, you can choose one size bigger.
Insole length is usually 0-15 mm longer than foot length for normal shoes.