YummyData, also known in Japanese as Umaka Data, is a research service that helps the biomedical community find and assess SPARQL endpoints and RDF datasets. It maintains a curated directory of relevant data resources and monitors them over time, helping researchers and other data consumers choose endpoints that are available, current, compliant, and useful.

The service tracks indicators including uptime, update activity, data volume, performance, and standards support. It also checks for features such as VoID descriptions, license information, SPARQL 1.1 support, and CORS compatibility. YummyData brings these and other measures together in its Umaka Score, which evaluates endpoints across availability, freshness, operation, usefulness, validity, and performance, with rankings from A to E. The site provides dashboards, ranked endpoint lists, endpoint search, and link graph tools, alongside details such as endpoint status and data-entry counts. A GitHub-based forum supports discussions about individual endpoints, connecting data providers with users who have questions or encounter issues.