Japan, officially Nippon, a country off the east coast of Asia. It consists of four large islands—Honshu, Hokkaido, Kyushu, and Shikoku—and more than 3,300 smaller ones, including the Ryukyu chain. Japan is bounded on the north by the Sea of Okhotsk; on the east and south by the Pacific Ocean; on the southwest by the East China Sea; and on the west by the Sea of Japan. Neighboring countries on the Asian mainland are Russia, China, North Korea, and South Korea.

The area of Japan is 145,914 square miles (377,915 km2). Maximum length of the four main islands (northeast-southwest) is roughly 1,250 miles (2,000 km); width, 250 miles (400 km). Honshu, called the mainland by the Japanese, accounts for slightly more than 60 per cent of the country's total area. Next in size are Hokkaido, the northernmost island; Kyushu, the southernmost large island; and Shikoku.

Japan lost some of its possessions as a result of World War II. These included the southern part of the island of Sakhalin, the Kuril Islands, Manchuria, Korea, and Taiwan.