Saint Lucia is approximately 616 sq km, while Belgium is approximately 30,528 sq km, making Belgium 4,856% larger than Saint Lucia. Meanwhile, the population of Saint Lucia is ~166,487 people (11.6 million more people live in Belgium).
This to-scale map shows a size comparison of Saint Lucia compared to Belgium. For more details, see an in-depth quality of life comparison of Belgium vs. Saint Lucia using our country comparison tool.