The Schema Markup Validator checks the syntax and structure of your schema code, ensuring it aligns with schema.org specifications. It's crucial for catching initial errors. On the other hand, the Rich Results Test specifically focuses on how your schema markup qualifies for rich results in Google Search, providing insights into how it appears in search results. For Google integration and visual representation, prefer the Rich Results Test. Use both tools together to ensure technical correctness and effective integration with Google's search algorithms.