By land area among archipelagic countries, Japan is commonly ranked second in the world after Indonesia.
The Japanese archipelago stretches in an arc along the western Pacific and includes four principal islands—Honshu, Hokkaido, Kyushu, and Shikoku—plus thousands of smaller islands. Its total land area is about 378,000 square kilometres, placing it ahead of the Philippines by national land area.
Honshu contains more than half of Japan’s land area and is the country’s political, economic, and cultural core. Hokkaido is the second-largest Japanese island, while Kyushu and Shikoku are smaller but historically and geographically distinct. The country also includes island groups such as the Ryukyu and Izu-Ogasawara chains.
The ranking can cause confusion because “second-largest archipelago” is sometimes used informally to describe the Philippines, especially by island count or in general reference works. The wording “by land area” points instead to Japan. Canada and Russia contain enormous island groups, including parts of the Arctic, but are not usually ranked as archipelagic countries in this comparison.