New Mexico is about 437 times bigger than Singapore.

Singapore is approximately 719 sq km, while New Mexico is approximately 314,310 sq km, making New Mexico 43,603% larger than Singapore. Meanwhile, the population of Singapore is ~5.9 million people (3.9 million fewer people live in New Mexico).
Tip: This to-scale comparison of Singapore vs. New Mexico uses the Mercator projection, which distorts the size of regions near the poles.