Nine-inch pizza is generally suitable for 2-3 people, which varies from person to person and has a great relationship with food intake. Pizza is named after its diameter, 1 inch is equal to 2.54 cm, and the diameter of a nine-inch pizza is equal to 9×2.54 and 22.86 cm, which is about as big as a normal western dish and suitable for 2-3 people. Pizza is the diameter, which can be obtained by multiplying the inch diameter by 2.54 when converted into centimeters. For example, the diameter of an eight-inch pizza is eight inches, which is 8 times 2.54 in centimeters, that is, 20.32 centimeters. In the actual situation, it is necessary to evaluate whether 9-inch pizza is enough for a certain number of people according to the specific situation.