The map above shows Japan and Northern Ireland side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Japan vs Northern Ireland Geography
Land area: Japan has a land area of 140,752 square miles (364,546 km²), while Northern Ireland has 5,236 square miles (13,562 km²). Japan's land area is 26.9 times larger than Northern Ireland's.
Total area: Japan: 145,937 square miles (377,975 km²) vs Northern Ireland: 5,456 square miles (14,130 km²), including inland and coastal water. Japan's total area is 26.7 times larger than Northern Ireland's.
Length: Japan is 1,557 miles (2,505 km) long from north to south; Northern Ireland is 83 miles (134 km). Japan's north-south length is 18.8 times longer than Northern Ireland's.
Width: Japan spans 1,568 miles (2,524 km) east to west; Northern Ireland spans 107 miles (173 km). Japan's east-west width is 14.7 times wider than Northern Ireland's.
Highest point: Japan's highest point is Mount Fuji at 12,388 feet (3,776 m); Northern Ireland's is Slieve Donard at 2,789 feet (850 m). Mount Fuji is 9,599 feet higher than Slieve Donard.
Lowest point: Japan's lowest point is Hachirogata at -13 feet; Northern Ireland's is Irish Sea at 0 feet. Japan's lowest point is 13 feet lower.
Japan vs Northern Ireland Population and History
Population: Japan has a population of 122,680,000 (2026), while Northern Ireland has 1,905,000 (2022). Japan's population is 64.4 times larger than Northern Ireland's.
Population density: Japan: 871.6 people per square mile vs Northern Ireland: 363.8. Japan's population density is 2.4 times (140%) higher than Northern Ireland's.
Biggest city: Japan's biggest city is Tokyo with 13,515,271 people; Northern Ireland's is Belfast with 348,005. Tokyo's population is 38.8 times larger than Belfast's.
History: Japan: An independent state for over two millennia; the current constitution dates from 1947. Northern Ireland: A country within the United Kingdom; created by the partition of Ireland on May 3, 1921. In its current form, Japan is the older of the two by 1,261 years.
Japan vs Northern Ireland Economy
GDP: Japan's GDP is $4,435.2 billion (2025) vs Northern Ireland's $58.8 billion. Japan's economic output is 75.4 times larger than Northern Ireland's.
GDP per capita: Japan: $35,951 per person vs Northern Ireland: $30,686. Japan's GDP per capita is 1.2 times (17%) higher than Northern Ireland's.
Official Websites
Japan official website · Northern Ireland official website
More Size Comparisons
All Japan size comparisons · All Northern Ireland size comparisons
Area, elevation and boundary figures come from official national statistics and US Census Bureau and Natural Earth boundary data; US state population, economic, county and tax figures come from the US Census Bureau, the Bureau of Economic Analysis and the Tax Foundation. Figures are rounded and for general reference.