The map above shows United States and Illinois side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
United States vs Illinois Geography
Land area: United States has a land area of 3,533,467 square miles (9,151,637 km²), while Illinois has 55,513 square miles (143,778 km²). United States' land area is 63.7 times larger than Illinois'.
Total area: United States: 3,802,784 square miles (9,849,165 km²) vs Illinois: 57,913 square miles (149,995 km²), including inland and coastal water. United States' total area is 65.7 times larger than Illinois'.
Length: United States is 3,628 miles (5,839 km) long from north to south; Illinois is 390 miles (628 km). United States' north-south length is 9.3 times (830%) longer than Illinois'.
Width: United States spans 4,824 miles (7,763 km) east to west; Illinois spans 283 miles (456 km). United States' east-west width is 17.0 times wider than Illinois'.
Highest point: United States's highest point is Denali at 20,308 feet (6,190 m); Illinois's is Charles Mound at 1,232 feet (376 m). Denali is 19,076 feet higher than Charles Mound.
Lowest point: United States's lowest point is Death Valley at -279 feet; Illinois's is Mississippi River at 292 feet. United States's lowest point is 571 feet lower.
United States vs Illinois Population and History
Population: United States has a population of 340,110,988 (2024), while Illinois has 12,710,158 (2024). United States' population is 26.8 times larger than Illinois'.
Population density: United States: 96.3 people per square mile vs Illinois: 229.0. Illinois' population density is 2.4 times (138%) higher than United States'.
Biggest city: United States's biggest city is New York with 8,478,072 people; Illinois's is Chicago with 2,721,308. New York's population is 3.1 times (212%) larger than Chicago's.
Largest metro area: United States's largest metropolitan area is New York-Newark-Jersey City, NY-NJ metro area (19,940,274 people) vs Illinois's Chicago-Naperville-Elgin, IL-IN metro area (9,408,576). New York-Newark-Jersey City, NY-NJ metro area's population is 2.1 times (112%) larger than Chicago-Naperville-Elgin, IL-IN metro area's.
History: United States: Declared independence on July 4, 1776. Illinois: Admitted to the Union on December 3, 1818, as the 21st state. In its current form, United States is the older of the two by 42 years.
United States vs Illinois Economy
GDP: United States's GDP is $30,769.7 billion (2025) vs Illinois's $1,148.1 billion. United States' economic output is 26.8 times larger than Illinois'.
GDP per capita: United States: $89,599 per person vs Illinois: $90,330. United States and Illinois have about the same GDP per capita.
Official Websites
United States official website · Illinois official website
More Size Comparisons
All United States size comparisons · All Illinois 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.