So I'm starting to sell some cakes from my kitchen and I'm slowly working out the pricing and serving guidelines.  I've decided I want to go off of these suggestions:

But I'm still confused....a sheet cake 'party size' will be 2x2x2, but do you still charge the same for a party size off a round, which would be probably 2x2x4??  And do you layer the square pans like the rounds or treat them like a sheet?  What's the industry norm, here.  Thanks!!!

You will need to price according to the serving. I am a preservative and artificial color/flavor free bakery. My primary cake business are dessert cakes.  I do have folks ordering bridal cakes and special party cake requiring specialized decorations, and those are charged according to servings/decoration/presentation.  My dessert cake line has basic bakery style frosting and can be ordered in "Celebration" or "Event" size.  My  "Celebration" size cakes are 2 layers of cake with one layer of frosting and are about 2" in height. These are designed to be cut in the standard pie shaped slices most folks are used to in either a very generous portion or a sensible portion.   The "Event" cake size is 4 layers of cake with 3 layers of filling and are about 4" tall.  These are meant to be cut in the wedding standard of 1x2x4.  I charge for the most servings that could be cut from that particular sized cake and provide a chart showing  how to cut the cake depending on the type ordered.  With special order cakes, I always provide a guide when the cake is picked up/delivered on how to cut the cake to achieve the number of servings the cake should be capable of feeding.  Many thanks to indydebi, as her cake cutting guidelines for cutting the cake in strips is what I use and base servings from for my "Event" and special order cakes.

Standard refers to 1x2x4 inches, so it is 8 cubic inches of cake. You should adopt one price "size" so that no one feels the event dictates the price. The customer feels ripped off. Wedding or BDay doesn't matter--- it is the SIZE of the cake I make. 

Thinking about a 1950's big 'ol wedge of cake, where an 8" round cake is cut into 8 wedges (assuming 4' high) is actually 25 cubic inches of cake! You know---- the pass around size hunk sold at some restaurants for $8 or more? More like 3 servings by industry standards today. 

You should use the wedding standard size as your pricing size. That is based on a full dinner being served, and the cake being served as a small plated dessert. You then need to recommend MORE servings if it is a "drink and cake party" (celebration), where people will expect a bit more generous serving in lieu of a full meal.

Like ordering an 8 slice pizza. Do you cut them in half and serve 16 "appetizer" servings, or 8 single slice servings, or only 4 "let's eat" servings? You pay for the pizza's 8 slices, and the hostess decides how it is served. You, should make recommendations about how much cake the guests are expected to eat based on the type of event and other foods served.

I once ordered a full sheet cake for 15 teenagers at a swim party. 96 "wedding" servings, 64 "party" servings, but really the 15 kids pretty much killed it all. LOL. (YUP, Costco... but the teenagers were fine with that!). I still paid for the full sheet cake, regardless of how I served it. 

PS. I don't think the chart you posted makes sense for a customer. Is a half sheet cake 108, 54, or 36 servings?If you charge $3 per serving, the same cake costs $324 to $108???

Price per wedding cake servings, as is industry standard and recommend the number (or larger) servings the hostess may choose to offer. 

I agree with Johnson6ofus that for cakes where you will be designing and providing a custom decorated cake, a uniformity of serving size, like sizing to wedding industry standard serving size of 1x2x4 is a necessity.  This allows you to work out your costs and cake pricing for your cakes + decorating.  What you will provide will be dependent on the type of bakery/caking business you are intending to have. 

The only time I have difference in cutting is when a client orders one of my bakery line cakes, where the decoration is my standard bakery decoration , only allowing cake/frosting flavor selections.  The Dessert Cake line come ins celebration size and event size and is cut according to the size ordered for the cake.

Thank you! The chart I posted, I mean to pick one size and base off that. But for the serving size....1×2×4 for a layer cake since it is 4" tall, ok I get. What about a sheetcake that is 2" tall? Assume cutting pieces 2x2×2"? So it is the same cubic amount of cake?

yes... you got it!