How to choose correct size: 1, Our size is not standard US size, and it is only equal to foot length 2. The size standards from different countries and different manufacturers are different, your foot length is the only criterion for choosing size. 3. Foot length is not insole length, and it is also not the shoes inside length. Normally, Inside length > foot length 4. Please measure your foot length carefully. Method is showed on the pictures below. 5. Please choose the size according your foot length!