The easy, but not very helpful, answer is that “it depends”. Obviously, the type of cake and the other food being served may affect the sizing, however, as a rule of thumb, the following table gives an idea:
| Size (cm/Inches) | Sponge or Chocolate | Fruit | |||
| Round | Square | Round | Square | ||
| 13cm / 5″ | 7 | 8 | 14 | 16 | |
| 15cm / 6″ | 11 | 14 | 22 | 27 | |
| 18cm/ 7″ | 15 | 20 | 30 |
40 | |
| 20cm / 8″ | 20 |
27 | 40 | 54 | |
| 23cm / 9″ | 27 | 35 | 54 |
70 |
|
| 25cm / 10″ | 34 | 45 | 70 | 90 | |
| 28cm / 11″ | 43 | 56 | 86 | 112 | |
| 30cm / 12″ | 50 | 70 | 100 | 134 | |
