The map above shows South Dakota and South Australia side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
South Dakota vs South Australia Geography
Land area: South Dakota has a land area of 75,808 square miles (196,342 km²), while South Australia has 380,048 square miles (984,321 km²). South Australia's land area is 5.0 times (401%) larger than South Dakota's.
Total area: South Dakota: 77,116 square miles (199,729 km²) vs South Australia: 380,048 square miles (984,321 km²), including inland and coastal water. South Australia's total area is 4.9 times (393%) larger than South Dakota's.
Length: South Dakota is 443 miles (712 km) long from north to south; South Australia is 1,078 miles (1,735 km). South Australia's north-south length is 2.4 times (143%) longer than South Dakota's.
Width: South Dakota spans 371 miles (597 km) east to west; South Australia spans 825 miles (1,328 km). South Australia's east-west width is 2.2 times (122%) wider than South Dakota's.
Highest point: South Dakota's highest point is Black Elk Peak at 7,198 feet (2,194 m); South Australia's is Mount Woodroffe at 4,708 feet (1,435 m). Black Elk Peak is 2,490 feet higher than Mount Woodroffe.
Lowest point: South Dakota's lowest point is Big Stone Lake at 966 feet; South Australia's is Lake Eyre at -49 feet. South Australia's lowest point is 1,015 feet lower.
South Dakota vs South Australia Population and History
Population: South Dakota has a population of 924,669 (2024), while South Australia has 1,908,182 (2025). South Australia's population is 2.1 times (106%) larger than South Dakota's.
Population density: South Dakota: 12.2 people per square mile vs South Australia: 5.0. South Dakota's population density is 2.4 times (144%) higher than South Australia's.
Largest metro area: South Dakota's largest metropolitan area is Sioux Falls, SD-MN metro area (308,266 people) vs South Australia's Greater Adelaide (1,491,015). Greater Adelaide's population is 4.8 times (384%) larger than Sioux Falls, SD-MN metro area's.
History: South Dakota: Admitted to the Union on November 2, 1889, as the 40th state. South Australia: Became an Australian state at Federation on January 1, 1901; founded as a colony in 1836. In its current form, South Dakota is the older of the two by 12 years.
South Dakota vs South Australia Economy
GDP: South Dakota's GDP is $76.8 billion (2024) vs South Australia's $100.2 billion. South Australia's economic output is 1.3 times (30%) larger than South Dakota's.
GDP per capita: South Dakota: $83,052 per person vs South Australia: $52,511. South Dakota's GDP per capita is 1.6 times (58%) higher than South Australia's.
Official Websites
South Dakota official website · South Australia official website
More Size Comparisons
All South Dakota size comparisons · All South Australia 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.