We recommend you check the size chart. When accessing the product sheet you will see, on the right-hand side, the table with all available sizes. European sizing will be shown by default, marked with the abbreviation EU.
If you select 8.5 in the US sizing table, for example, and then go back to either the EU (European system) or UK (British system) table, you can see what your US 8.5 is equivalent to. You also have the option to verify how many centimeters is the size you selected, by clicking on the acronym CM.
Please note that if the model is not specified as "Women" the size shown will be for men.
If you are still doubting, we always recommend opting for the size in centimeters to ensure you measure it correctly. It is also useful to check the size on a shoe you already own – most sneakers have an inner label with the model's information and sizing.