How this wedding cake calculator works
Wedding cake cost comes down to two numbers: how many servings the cake gives, and what your baker charges per serving. The first one is just geometry, so we work it out exactly. The second one you get from your bakery.
- Find the top area of each tier. A round tier is π × radius², so a 10 inch round is about 78.5 square inches. A square tier is side × side.
- Divide by the slice size. A wedding slice takes up 2 square inches (1 × 2 in). A party slice takes 3 (1.5 × 2 in). Round down to whole slices.
- Add the tiers and any sheet cakes. Sheet cakes are worked out the same way, using width × length.
- Multiply by the price per slice to get the cost.
Wedding cake servings chart
Calculated with the method above, for standard 4 inch tall tiers:
| Tier size | Round: wedding | Round: party | Square: wedding | Square: party |
|---|---|---|---|---|
| 6 inch | 14 | 9 | 18 | 12 |
| 8 inch | 25 | 16 | 32 | 21 |
| 10 inch | 39 | 26 | 50 | 33 |
| 12 inch | 56 | 37 | 72 | 48 |
| 14 inch | 76 | 51 | 98 | 65 |
| 16 inch | 100 | 67 | 128 | 85 |
Sheet cake servings
| Sheet | Size | 2 layers: wedding | 2 layers: party | 1 layer: wedding |
|---|---|---|---|---|
| Quarter sheet | 9 × 13 in | 58 | 39 | 29 |
| Half sheet | 12 × 18 in | 108 | 72 | 54 |
| Full sheet | 18 × 24 in | 216 | 144 | 108 |
Pan sizes vary a little between bakeries. Some call an 11 × 15 inch pan a half sheet, for example. Choose "Custom size" in the calculator to enter your baker's exact dimensions.
Worked example: 120 guests with a cutting cake and a sheet cake
A popular way to save money is a small, decorated cake for the photos and the cutting, plus a plain sheet cake in the kitchen that the caterer slices for everyone.
| Cake | Math | Servings |
|---|---|---|
| 8 inch round tier | 50.3 sq in ÷ 2 | 25 |
| 6 inch round tier | 28.3 sq in ÷ 2 | 14 |
| Half sheet, 2 layers | 12 × 18 = 216 sq in ÷ 2 | 108 |
| Total | 147 |
That covers 120 guests with 27 slices to spare. Now the cost. Suppose your baker quotes $6 a slice for the decorated tiers and $3 a slice for the sheet cake. (These are example prices only, not averages.) That gives 39 × $6 = $234 for the tiers and 108 × $3 = $324 for the sheet, so $558 in total.
Tips to plan the right amount of cake
- Ask how your baker prices. Most quote per slice, but fondant, sugar flowers, extra flavors and delivery can change the rate or add a fee.
- Check for a cake-cutting fee. Some venues charge one to slice and serve a cake from an outside baker. Ask before you book.
- Not everyone eats cake. If you also have a dessert table, you rarely need a full slice for every guest. Talk it through with your caterer.
- Saving the top tier? Remove it from the tiers list so the servings count matches what you will actually serve.
- Plan the rest of the menu too. Our catering cost per person tool and wedding budget calculator help you see how the cake fits into the bigger picture.