Ordering cake for a crowd is guesswork for most people, and guessing wrong goes one of two ways — running out in front of your guests, or eating sheet cake for a week. The industry has standard numbers for this. They're worth knowing before you order anything.
The numbers, by cake size
Serving counts depend on how the cake gets cut. A party slice is roughly 1½ by 2 inches. A wedding slice is about 1 by 2 inches — noticeably slimmer, which is why the same cake stretches further at a wedding.
- 6-inch round — about 12 servings
- 8-inch round — about 20 party slices, or 24 wedding slices
- 10-inch round — about 28 party slices, or 38 wedding slices
- 12-inch round — about 40 party slices, or 56 wedding slices
Stacked tiers add up the same way. A classic three-tier of 6, 8, and 10 inches serves roughly 74. Going 6, 8, and 12 gets you to about 92.
Watch for this when comparing quotes: if one baker quotes party slices and another quotes wedding slices, the second is describing a smaller portion. Always ask which they mean before assuming one cake is a better deal than the other.
Five things that shift the math
- Other desserts on the table. If there are cookies, brownies, or a dessert spread alongside the cake, plan for meaningfully fewer cake servings. People take one dessert, not all of them.
- Kids. A party full of children eats far less cake than the headcount suggests, and a lot of it ends up on plates.
- Time of day. Cake after a full dinner gets picked at. Cake at an afternoon party gets eaten.
- Whether you want leftovers. Some people specifically want cake for the next day. Say so and it gets built in rather than left to chance.
- The top tier. Couples who plan to freeze their top tier for their first anniversary shouldn't count it in the serving total.
When cupcakes make more sense
For a party where you just need everyone to get dessert, cupcakes are often the simpler answer — one per guest, no cutting, no plates and forks, no math. Signature and classic cupcakes are $30 per dozen, so a 40-person party is a little over three dozen. More on choosing between them →
A practical approach
Order for the number of people you actually expect to eat cake, not the number invited. For most parties that's around 75 to 80 percent of the guest list. Then decide deliberately whether you want leftovers, and size up only if you do.
Or skip the arithmetic entirely: send your headcount and what else is being served, and Kelsey will tell you what size makes sense. That conversation costs nothing and prevents both failure modes.
Not sure what size you need?
Send your guest count and the occasion — Kelsey will recommend a size and confirm pricing within 24 hours.
Request an OrderRelated: how far in advance to order, what a wedding cake costs, and the full menu.