Papua New Guinea is about 1.7 times bigger than Colorado.

Colorado is approximately 268,627 sq km, while Papua New Guinea is approximately 462,840 sq km, making Papua New Guinea 72% larger than Colorado. Meanwhile, the population of Colorado is ~5.0 million people (4.6 million more people live in Papua New Guinea).
Tip: This to-scale comparison of Colorado vs. Papua New Guinea uses the Mercator projection, which distorts the size of regions near the poles.