District of Columbia is about 2.2 times smaller than Saint Vincent and the Grenadines.

Saint Vincent and the Grenadines is approximately 389 sq km, while District of Columbia is approximately 177 sq km, making District of Columbia 45.5% the size of Saint Vincent and the Grenadines. Meanwhile, the population of Saint Vincent and the Grenadines is ~100,969 people (500,754 more people live in District of Columbia).
Tip: This to-scale comparison of Saint Vincent and the Grenadines vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.