Short answer: A 7-inch pizza is a personal size — about 18 cm across, usually 4 slices. It is not a “small” at Domino's or Pizza Hut (those start near 10 inch). “7 inches pizza means” in search is this diameter, not a chain name.
| Size | Diameter | Approx. area | Typical slices |
|---|---|---|---|
| 7 inch | 18 cm | ~38 sq in | 4 |
| 10 inch (small) | 25 cm | ~79 sq in | 6 |
| 12 inch (medium) | 30 cm | ~113 sq in | 8 |
| 14 inch (large) | 36 cm | ~154 sq in | 8 |
A large 14-inch pie has about four times the pizza of a 7-inch, not twice. If you are feeding more than one person, jump sizes; do not order two 7-inch pies expecting a large.
Personal pan pizzas at some chains are 6–8 inches. Frozen “personal” pies are often 7 inch. For large-slice counts see how many slices in a large pizza.