Oklahoma is around the same size as North Dakota.

North Dakota is approximately 178,647 sq km, while Oklahoma is approximately 177,847 sq km, making Oklahoma 99.55% the size of North Dakota. Meanwhile, the population of North Dakota is ~799,358 people (3.3 million more people live in Oklahoma).
Tip: This to-scale comparison of North Dakota vs. Oklahoma uses the Mercator projection, which distorts the size of regions near the poles.
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