Delaware is about 29 times bigger than District of Columbia.

District of Columbia is approximately 177 sq km, while Delaware is approximately 5,060 sq km, making Delaware 2,759% larger than District of Columbia. Meanwhile, the population of District of Columbia is ~601,723 people (296,211 more people live in Delaware).
Tip: This to-scale comparison of District of Columbia vs. Delaware uses the Mercator projection, which distorts the size of regions near the poles.