The map above shows Idaho and Ontario side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Idaho vs Ontario Geography
Land area: Idaho has a land area of 82,645 square miles (214,051 km²), while Ontario has 354,342 square miles (917,741 km²). Ontario's land area is 4.3 times (329%) larger than Idaho's.
Total area: Idaho: 83,569 square miles (216,441 km²) vs Ontario: 415,598 square miles (1,076,395 km²), including inland and coastal water. Ontario's total area is 5.0 times (397%) larger than Idaho's.
Length: Idaho is 483 miles (778 km) long from north to south; Ontario is 1,085 miles (1,747 km). Ontario's north-south length is 2.2 times (125%) longer than Idaho's.
Width: Idaho spans 352 miles (566 km) east to west; Ontario spans 1,013 miles (1,630 km). Ontario's east-west width is 2.9 times (188%) wider than Idaho's.
Highest point: Idaho's highest point is Borah Peak at 12,631 feet (3,850 m); Ontario's is Ishpatina Ridge at 2,274 feet (693 m). Borah Peak is 10,357 feet higher than Ishpatina Ridge.
Lowest point: Idaho's lowest point is Snake River at 718 feet; Ontario's is Hudson Bay at 0 feet. Ontario's lowest point is 718 feet lower.
Idaho vs Ontario Population and History
Population: Idaho has a population of 2,001,619 (2024), while Ontario has 16,136,480 (2026). Ontario's population is 8.1 times (706%) larger than Idaho's.
Population density: Idaho: 24.2 people per square mile vs Ontario: 45.5. Ontario's population density is 1.9 times (88%) higher than Idaho's.
Biggest city: Idaho's biggest city is Boise with 237,963 people; Ontario's is Toronto with 2,794,356. Toronto's population is 11.7 times larger than Boise's.
Largest metro area: Idaho's largest metropolitan area is Boise City, ID metro area (845,877 people) vs Ontario's Toronto CMA (6,202,225). Toronto CMA's population is 7.3 times (633%) larger than Boise City, ID metro area's.
History: Idaho: Admitted to the Union on July 3, 1890, as the 43rd state. Ontario: Joined Confederation on July 1, 1867, as one of the four founding provinces. In its current form, Ontario is the older of the two by 23 years.
Idaho vs Ontario Economy
GDP: Idaho's GDP is $129.0 billion (2024) vs Ontario's $873.9 billion. Ontario's economic output is 6.8 times (577%) larger than Idaho's.
GDP per capita: Idaho: $64,457 per person vs Ontario: $54,132. Idaho's GDP per capita is 1.2 times (19%) higher than Ontario's.
Official Websites
Idaho official website · Ontario official website
More Size Comparisons
All Idaho size comparisons · All Ontario 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.