The map above shows Iowa and Oklahoma side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Iowa vs Oklahoma Geography
Land area: Iowa has a land area of 55,854 square miles (144,660 km²), while Oklahoma has 68,597 square miles (177,665 km²). Oklahoma's land area is 1.2 times (23%) larger than Iowa's.
Total area: Iowa: 56,273 square miles (145,746 km²) vs Oklahoma: 69,899 square miles (181,038 km²), including inland and coastal water. Oklahoma's total area is 1.2 times (24%) larger than Iowa's.
Length: Iowa is 216 miles (347 km) long from north to south; Oklahoma is 533 miles (857 km). Oklahoma's north-south length is 2.5 times (147%) longer than Iowa's.
Width: Iowa spans 335 miles (539 km) east to west; Oklahoma spans 490 miles (789 km). Oklahoma's east-west width is 1.5 times (46%) wider than Iowa's.
Highest point: Iowa's highest point is Hawkeye Point at 1,669 feet (509 m); Oklahoma's is Black Mesa at 4,980 feet (1,518 m). Black Mesa is 3,311 feet higher than Hawkeye Point.
Lowest point: Iowa's lowest point is Mississippi River at 480 feet; Oklahoma's is Little River at 289 feet. Oklahoma's lowest point is 191 feet lower.
Iowa vs Oklahoma Population and History
Population: Iowa has a population of 3,241,488 (2024), while Oklahoma has 4,095,393 (2024). Oklahoma's population is 1.3 times (26%) larger than Iowa's.
Population density: Iowa: 58.0 people per square mile vs Oklahoma: 59.7. Iowa and Oklahoma have about the same population density.
Biggest city: Iowa's biggest city is Des Moines with 213,096 people; Oklahoma's is Oklahoma City with 712,919. Oklahoma City's population is 3.3 times (235%) larger than Des Moines'.
Largest metro area: Iowa's largest metropolitan area is Omaha, NE-IA metro area (1,001,010 people) vs Oklahoma's Oklahoma City, OK metro area (1,497,821). Oklahoma City, OK metro area's population is 1.5 times (50%) larger than Omaha, NE-IA metro area's.
History: Iowa: Admitted to the Union on December 28, 1846, as the 29th state. Oklahoma: Admitted to the Union on November 16, 1907, as the 46th state. In its current form, Iowa is the older of the two by 61 years.
Iowa vs Oklahoma Economy
GDP: Iowa's GDP is $265.8 billion (2024) vs Oklahoma's $263.7 billion. Iowa and Oklahoma have about the same economic output.
GDP per capita: Iowa: $81,998 per person vs Oklahoma: $64,388. Iowa's GDP per capita is 1.3 times (27%) higher than Oklahoma's.
Average income: Iowa: $65,225 vs Oklahoma: $63,708 average income per person (per capita personal income). Iowa and Oklahoma have about the same average income.
Iowa vs Oklahoma Counties
Number of counties: Iowa has 99 counties, while Oklahoma has 77. Iowa's county count is 1.3 times (29%) higher than Oklahoma's.
Biggest county by area: Iowa's largest county is Kossuth County at 973 square miles; Oklahoma's is Osage County at 2,247 square miles. Osage County's land area is 2.3 times (131%) larger than Kossuth County's.
Smallest county by area: Iowa: Dickinson County (381 sq mi) vs Oklahoma: Marshall County (372 sq mi). Dickinson County and Marshall County have about the same land area.
Most populous county: Iowa: Polk County (516,185 people) vs Oklahoma: Oklahoma County (816,490 people). Oklahoma County's population is 1.6 times (58%) larger than Polk County's.
Least populous county: Iowa: Adams County (3,606 people) vs Oklahoma: Cimarron County (2,133 people). Adams County's population is 1.7 times (69%) larger than Cimarron County's.
Richest county: Iowa: Mitchell County ($98,211 per capita income) vs Oklahoma: Washington County ($126,749). Washington County's income is 1.3 times (29%) richer than Mitchell County's.
Poorest county: Iowa: Decatur County ($46,134 per capita income) vs Oklahoma: Atoka County ($38,709). Decatur County's income is 1.2 times (19%) richer than Atoka County's.
Iowa vs Oklahoma Taxes
State income tax: Iowa has a top income tax rate of 3.8%, while Oklahoma has a top income tax rate of 4.5%. Oklahoma's top rate is 0.7 percentage points higher.
Property tax: Iowa: 1.29% effective rate vs Oklahoma: 0.75% of home value per year. Iowa's rate is 0.54 percentage points higher.
Sales tax: Iowa: 6.94% combined state and average local rate vs Oklahoma: 9.06%. Oklahoma's combined rate is 2.12 percentage points higher.
Official Websites
Iowa official website · Oklahoma official website
More Size Comparisons
All Iowa size comparisons · All Oklahoma 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.