Aruba is around the same size as District of Columbia.

District of Columbia is approximately 177 sq km, while Aruba is approximately 180 sq km, making Aruba 2% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (479,403 fewer people live in Aruba).
Tip: This to-scale comparison of District of Columbia vs. Aruba uses the Mercator projection, which distorts the size of regions near the poles.