Ceramic 26cm Large Pie Dish

I have just bought this product online, which is called a 30cm pie dish, and opened the packaging. However, the width from outside edge to outside edge is actually 26cm and when you deduct the 3cm width of the rim the inside measurement is only 23cm! It is true that, when you click on "details" the width is shown as 26cm but this description is very misleading and rather disappointing.