data japan 2024The 2025 population density in Japan is 338 people per Km2 (875 people per mi2), calculated on a total land area of 364,555 Km2 (140,755 sq. miles). Largest Cities in Japan City NameJapan in international parison 17 Basic Statistic Countries with the lowest fertility rates 2025 Basic Statistic Median age of the population in the top 20