The size of a pizza is calculated according to its diameter. A 9-inch pizza means its diameter is 9 inches. The conversion ratio between inches and common centimeters is: 1 inch ≈2.54 cm, so the diameter of a 9-inch pizza is about 9*2.54=22.86 cm.

Due to hand-made, pizza ingredients, baking temperature and other factors, the actual size will be different from the theoretical size, but the overall difference will not be too big, which is a normal phenomenon.

Extended data

Comparison of common pizza sizes

1, 6-inch pizza-15.24 cm.

2, 7-inch pizza-17.78 cm.

3, 8-inch pizza-20.32 cm.

4, 9-inch pizza-22.86 cm.

5, 10 inch pizza-25.4 cm.

6. 1 1 inch pizza-27.94 cm.

7. 12 inch pizza-30.48 cm.

8. 13 inch pizza-33.02 cm.

9. 14 inch pizza-35.56 cm.

10, 15 inch pizza-38.1cm.