What Is the Standard Size of a Dinner Plate?

The modern dinner plate reflects an increase in size by approximately 23 percent since 1900, when the average dinner plate measured a little over 9 inches in diameter. The increased size in dinner plates has led to larger portion sizes, which is a contributing factor to the obesity epidemic affecting many in the West. Even a plate size from the 1950s, when the average diameter was just under 10 inches, would reflect a healthy change over the larger plates of today.