Montana is around the same size as Republic of the Congo.

Republic of the Congo is approximately 342,000 sq km, while Montana is approximately 376,979 sq km, making Montana 10% larger than Republic of the Congo. Meanwhile, the population of Republic of the Congo is ~5.5 million people (4.6 million fewer people live in Montana).
Tip: This to-scale comparison of Republic of the Congo vs. Montana uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.