Wyoming is about 1.4 times bigger than North Dakota.

North Dakota is approximately 178,647 sq km, while Wyoming is approximately 251,489 sq km, making Wyoming 41% larger than North Dakota. Meanwhile, the population of North Dakota is ~672,591 people (108,965 fewer people live in Wyoming).
Tip: This to-scale comparison of North Dakota vs. Wyoming uses the Mercator projection, which distorts the size of regions near the poles.