The map above shows Idaho and Western Australia side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Idaho vs Western Australia Geography
Land area: Idaho has a land area of 82,645 square miles (214,051 km²), while Western Australia has 975,685 square miles (2,527,013 km²). Western Australia's land area is 11.8 times larger than Idaho's.
Total area: Idaho: 83,569 square miles (216,441 km²) vs Western Australia: 975,685 square miles (2,527,013 km²), including inland and coastal water. Western Australia's total area is 11.7 times larger than Idaho's.
Length: Idaho is 483 miles (778 km) long from north to south; Western Australia is 1,590 miles (2,558 km). Western Australia's north-south length is 3.3 times (229%) longer than Idaho's.
Width: Idaho spans 352 miles (566 km) east to west; Western Australia spans 1,286 miles (2,069 km). Western Australia's east-west width is 3.7 times (265%) wider than Idaho's.
Highest point: Idaho's highest point is Borah Peak at 12,631 feet (3,850 m); Western Australia's is Mount Meharry at 4,098 feet (1,249 m). Borah Peak is 8,533 feet higher than Mount Meharry.
Lowest point: Idaho's lowest point is Snake River at 718 feet; Western Australia's is Indian Ocean at 0 feet. Western Australia's lowest point is 718 feet lower.
Idaho vs Western Australia Population and History
Population: Idaho has a population of 2,001,619 (2024), while Western Australia has 3,061,672 (2025). Western Australia's population is 1.5 times (53%) larger than Idaho's.
Population density: Idaho: 24.2 people per square mile vs Western Australia: 3.1. Idaho's population density is 7.8 times (681%) higher than Western Australia's.
Largest metro area: Idaho's largest metropolitan area is Boise City, ID metro area (845,877 people) vs Western Australia's Greater Perth (2,452,765). Greater Perth's population is 2.9 times (190%) larger than Boise City, ID metro area's.
History: Idaho: Admitted to the Union on July 3, 1890, as the 43rd state. Western Australia: Became an Australian state at Federation on January 1, 1901; founded as a colony in 1829. In its current form, Idaho is the older of the two by 11 years.
Idaho vs Western Australia Economy
GDP: Idaho's GDP is $129.0 billion (2024) vs Western Australia's $304.6 billion. Western Australia's economic output is 2.4 times (136%) larger than Idaho's.
GDP per capita: Idaho: $64,457 per person vs Western Australia: $99,488. Western Australia's GDP per capita is 1.5 times (54%) higher than Idaho's.
Official Websites
Idaho official website · Western Australia official website
More Size Comparisons
All Idaho size comparisons · All Western 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.