"How many will it feed?" is the first question a customer asks and the one most likely to lose you money if you guess.
The honest answer is that it depends less on the cake than on how it is cut. The same two-tier cake can serve 38 people or 29, and both numbers are correct.
The short answer
For the two most common two-tier combinations, cut at standard portion sizes:
| Tiers | Wedding portions (1"×2") | Party portions (1.5"×2") |
|---|---|---|
| 6" + 8" | 38 | 29 |
| 8" + 10" | 62 | 48 |
| 10" + 12" | 94 | 68 |
Those are for round tiers of standard depth. Square tiers of the same nominal size give noticeably more, because you are packing a grid into a square rather than a circle.
Why portion size changes everything
A "serving" is not a fixed thing. There are four sizes in common use:
- Finger or coffee (1"×1") — small slices handed round with tea. The most servings per cake by a wide margin.
- Wedding (1"×2") — the traditional wedding slice: tall, narrow, served on a small plate.
- Party (1.5"×2") — what most people picture as a slice of birthday cake. This is the sensible default for celebration cakes.
- Dessert (2"×2") — a generous plated portion, usually the only sweet course.
An 8" round gives 48 finger portions, 24 wedding portions, 20 party portions or 12 dessert portions. Same cake. Four answers.
This is why a quote should always say which portion size it assumes. "Serves 38" on its own is a promise you may not be able to keep.
What to ask the customer
Before you quote a tiered cake, three questions settle the size:
- How many guests? Not "how many invited" — how many will actually be there.
- Is there another dessert? If the cake is the dessert, quote dessert portions. If it is cut after a full meal, wedding or party portions are right.
- Do they want leftovers? Some customers want a tier to take home or freeze. That changes the answer by a whole tier.
A useful rule: if the cake is being cut by venue staff, expect wedding portions. If it is being cut by the customer's aunt in a kitchen, expect party portions or larger — and quote accordingly.
The trap: quoting servings but pricing per cake
Here is where money leaks. A baker quotes "serves 60" and prices the cake at what feels reasonable. But a 60-serving cake is not twice the work of a 30-serving cake — it is more than twice, because a larger tier needs more support, more baking time, more ganache and more careful transport.
Price from your real costs and your real hours, then check the per-serving number as a sanity test. If your 8"+10" comes out at $4.20 a serving and your 6"+8" at $6.10, that gap is telling you something about your labour estimate on the smaller cake.
We wrote a longer piece on this: how to price a celebration cake for profit.
Shapes other than round
Round is the reference. For the same nominal size:
- Square gives roughly a third more than round, because the corners are usable cake.
- Heart gives about a quarter less.
- Hexagon sits close to round, a little under.
- Petal gives about 30% less — those scalloped edges cost you servings.
If you are quoting a shaped cake, work out the round number first and then adjust, rather than guessing from scratch.
Do not do this in your head at 11pm
Serving maths is exactly the kind of thing that should not depend on how tired you are. Bake Boost has a built-in cake cutting and servings guide — pick the shape, the sizes and the portion, and it gives you the number and prints a cutting guide you can hand to the venue. It is on every plan, including Essentials.
There is a full walkthrough in the docs: how many servings is my cake?