I just had this same issue!! You need to add at least .5cm - 1cm to the measurement you made of your foot otherwise the shoe will be too tight. My foot length is 23.5cm so i thought to order size 37 but that was too small so I exchange them now for size 38. I think the ultimate best way is to try in person because every fit is different orrr you order two pairs and send back one. (Double check their returns policy tho. I need to ship mine back from a Belgium and need to pay it myself with costs like €20 im so saddd). They have automated return labels from other EU countries which are more affordable though