Round pizza area is π × radius². That means an 18-inch pizza contains more than twice the surface area of a 12-inch pizza, even though the diameter is only 50 percent larger.
| Diameter | Area | Compared with 12-inch |
|---|---|---|
| 8 inches | 50.3 in² | 44% |
| 10 inches | 78.5 in² | 69% |
| 12 inches | 113.1 in² | 100% |
| 14 inches | 153.9 in² | 136% |
| 16 inches | 201.1 in² | 178% |
| 18 inches | 254.5 in² | 225% |
| 20 inches | 314.2 in² | 278% |
Why two small pizzas may still make sense
Two pizzas allow different toppings, create more outer crust and may fit dietary needs better. Area is only one part of the decision.
Rectangular pizzas
For a rectangular pan, multiply length by width. A 10-by-14-inch pan has 140 square inches of surface area.
Thickness and toppings
Deep or pan pizza can provide more food per square inch. Price-per-area comparison works best between similar crust styles.
Slice count
Cutting a pizza into 12 slices instead of 8 does not create more pizza. Smaller pieces can still help with sharing and portion control.
A useful mental shortcut
Moving from 12 to 16 inches increases diameter by one-third but area by about 78 percent. Moving from 16 to 18 inches adds about 27 percent more area. This is why visual impressions at the menu can be misleading.
Square and rectangular pans
A 10-by-14-inch rectangle contains 140 square inches. Compare it with a 14-inch round at about 154 square inches, then account for thickness and edge crust. Rectangular pieces may also distribute corner and edge portions differently.