Oklahoma is about 1.5 times bigger than Pennsylvania.

Pennsylvania is approximately 116,075 sq km, while Oklahoma is approximately 177,847 sq km, making Oklahoma 53% larger than Pennsylvania. Meanwhile, the population of Pennsylvania is ~13.1 million people (8.9 million fewer people live in Oklahoma).
Tip: This to-scale comparison of Pennsylvania vs. Oklahoma uses the Mercator projection, which distorts the size of regions near the poles.
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