data japan 2023The 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 Data. Japan’s Fiscal 2025 Budget Reaches Record Hh of ¥114.4 Trillion Economy Politics Society Jan 13, 2025. With social security costs continuing to balloon due to an aging population