What are the sizes of a standard postcard and a continental postcard?

A standard postcard typically measures 4 inches by 6 inches (10.16 cm by 15.24 cm). In contrast, a continental postcard is larger, generally measuring 4.1 inches by 5.8 inches (10.5 cm by 14.8 cm), which is similar to A6 paper size. Both sizes are commonly used for mailing and personal correspondence.