North Dakota is about 248 times bigger than Singapore.

Singapore is approximately 719 sq km, while North Dakota is approximately 178,647 sq km, making North Dakota 24,740% larger than Singapore. Meanwhile, the population of Singapore is ~5.9 million people (5.2 million fewer people live in North Dakota).
Tip: This to-scale comparison of Singapore vs. North Dakota uses the Mercator projection, which distorts the size of regions near the poles.