When ordering a wedding cake, the size of the cake needed to feed the guests is based on the number of equal sized servings needed. Wedding cake servings are generally smaller than a piece of cake you might have at home after supper or a party.
A standard wedding cake serving size should measure about 1” wide x 2” long x 4” high. That is 1”x2”x4”= 8 cubic inches of cake. If a cake tier happens to only be 2” tall, then 2”x2”x2”= 8” piece would be the same serving amount as the standard wedding cake serving size.
Occasionally a wedding couple may want to serve a slightly larger piece as their standard serving. This is more common at weddings that only have a cake reception, without a meal. Since cake is the main food served, people will be hungrier than if they have a meal, too. So, it makes sense to serve a slightly larger slice to be more satisfying to them. This cake serving size can range from 1.5”x2”x 4”= 12 cubic inches to 2”x2”x4”= 16 cubic inches of cake, which is quite large. The later often being labeled a “party size” serving because it is served at a party without a meal or other food.
A cake should be ordered according to the number of guests AND the serving size one wants to provide. Not everyone will eat a piece of cake, but the number of guests attending will give you an idea of where to start sizing your cake.