I'm making a wedding cake where some of the tiers are shorter than my normal tier height and I'm wondering how you factor the serving sizes? Would it be the same or would you just calculate it to serve 1/2 the amount or....? Also, do I just ask the caterer to cut larger pieces out of the shorter tiers to ensure everyone gets the same amount of cake?

How much shorter? If it's 2" high instead of 4" high, it would serve half the amount and it would be appropriate to cut into 2"x2"x2" servings.

I leave a cake info sheet with all of my cakes. At the bottom is says how to cut the cake and what sizes the pieces should be. If there are multiple height cakes, then they are all listed.

2" cakes: 2x2"
3" cakes: 1x3"
4" cakes: 1x2"
5" cakes: 1x1.5"

A "serving" is 8 cubic inches of cake, so when the height changes, the other dimensions have to change too.

Perfect! Thank you both for your helpful input!!