Hello, If your foot length is 27.5 cm, according to the Adidas size chart, the size you should normally wear is 43 1/3 or 44. The fact that you normally wear size 44.5 - 45 may be due to the difference in patterns of different brands. While there is no general rule like “buy 1.5 sizes bigger” when it comes to football boots, some footballers might prefer half a size bigger for more comfort or to wear with socks. However, it is generally not recommended to go up by 1.5 sizes, as it is important for the cleats to fit snugly and provide control over the ball and performance. A crampon that is too big can slip in the foot and increase the risk of injury. If there is anything else, I would be happy to help you as Korayspor.