Baking
Cake Calculator
Find out how many cakes to bake for your guests, based on the pan you have and how big you cut the slices.
You need
4
8-inch round cakes
Each 8-inch round cake gives about 12 slices, so 4 cakes make 48 slices for 40 guests (8 spare).
Every pan size at a glance
| Pan | Slices per cake | Cakes for 40 guests |
|---|---|---|
| 6 in (15 cm) | 7 | 6 |
| 7 in (18 cm) | 9 | 5 |
| 8 in (20 cm) | 12 | 4 |
| 9 in (23 cm) | 15 | 3 |
| 10 in (25 cm) | 19 | 3 |
| 12 in (30 cm) | 28 | 2 |
| 14 in (36 cm) | 38 | 2 |
| 16 in (41 cm) | 50 | 1 |
How this is calculated
Slices per cake = the pan’s top area ÷ the area of one slice, rounded down. A round pan’s area is π × (diameter ÷ 2)²; square and sheet pans are length × width.
Slice sizes assume a cake about 4 in (10 cm) tall, which is two layers. Round cakes lose a little at the edges, so plan a few spare slices. For a tiered cake, add up the slices from each tier.
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