When choosing a cake base for an 8 inch cake, it's generally recommended to select a base that is 2 to 3 inches larger than the cake itself. This allows for ample space for icing or decorations, and also provides stability when moving the cake. Therefore, for an 8 inch cake, a 10 to 11 inch cake base would be an ideal choice. It's crucial to ensure that the base is sturdy and food-safe, as it not only supports the weight of the cake, but also comes into direct contact with it.