Saint Vincent and the Grenadines is about 553 times smaller than Guyana.

Guyana is approximately 214,969 sq km, while Saint Vincent and the Grenadines is approximately 389 sq km, making Saint Vincent and the Grenadines 0.18% the size of Guyana. Meanwhile, the population of Guyana is ~789,683 people (688,714 fewer people live in Saint Vincent and the Grenadines).
Tip: This to-scale comparison of Guyana vs. Saint Vincent and the Grenadines uses the Mercator projection, which distorts the size of regions near the poles.