Barbados is about 2.4 times bigger than District of Columbia.

District of Columbia is approximately 177 sq km, while Barbados is approximately 430 sq km, making Barbados 143% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (299,049 fewer people live in Barbados).
Tip: This to-scale comparison of District of Columbia vs. Barbados uses the Mercator projection, which distorts the size of regions near the poles.